2 * iterator/iterator.c - iterative resolver DNS query response module
4 * Copyright (c) 2007, NLnet Labs. All rights reserved.
6 * This software is open source.
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
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13 * this list of conditions and the following disclaimer.
15 * Redistributions in binary form must reproduce the above copyright notice,
16 * this list of conditions and the following disclaimer in the documentation
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21 * specific prior written permission.
23 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
24 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
25 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
26 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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28 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
29 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
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33 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
39 * This file contains a module that performs recursive iterative DNS query
44 #include "iterator/iterator.h"
45 #include "iterator/iter_utils.h"
46 #include "iterator/iter_hints.h"
47 #include "iterator/iter_fwd.h"
48 #include "iterator/iter_donotq.h"
49 #include "iterator/iter_delegpt.h"
50 #include "iterator/iter_resptype.h"
51 #include "iterator/iter_scrub.h"
52 #include "iterator/iter_priv.h"
53 #include "validator/val_neg.h"
54 #include "services/cache/dns.h"
55 #include "services/cache/infra.h"
56 #include "services/authzone.h"
57 #include "util/module.h"
58 #include "util/netevent.h"
59 #include "util/net_help.h"
60 #include "util/regional.h"
61 #include "util/data/dname.h"
62 #include "util/data/msgencode.h"
63 #include "util/fptr_wlist.h"
64 #include "util/config_file.h"
65 #include "util/random.h"
66 #include "sldns/rrdef.h"
67 #include "sldns/wire2str.h"
68 #include "sldns/str2wire.h"
69 #include "sldns/parseutil.h"
70 #include "sldns/sbuffer.h"
73 int UNKNOWN_SERVER_NICENESS = 376;
76 iter_init(struct module_env* env, int id)
78 struct iter_env* iter_env = (struct iter_env*)calloc(1,
79 sizeof(struct iter_env));
81 log_err("malloc failure");
84 env->modinfo[id] = (void*)iter_env;
86 lock_basic_init(&iter_env->queries_ratelimit_lock);
87 lock_protect(&iter_env->queries_ratelimit_lock,
88 &iter_env->num_queries_ratelimited,
89 sizeof(iter_env->num_queries_ratelimited));
91 if(!iter_apply_cfg(iter_env, env->cfg)) {
92 log_err("iterator: could not apply configuration settings.");
99 /** delete caps_whitelist element */
101 caps_free(struct rbnode_type* n, void* ATTR_UNUSED(d))
104 free(((struct name_tree_node*)n)->name);
110 iter_deinit(struct module_env* env, int id)
112 struct iter_env* iter_env;
113 if(!env || !env->modinfo[id])
115 iter_env = (struct iter_env*)env->modinfo[id];
116 lock_basic_destroy(&iter_env->queries_ratelimit_lock);
117 free(iter_env->target_fetch_policy);
118 priv_delete(iter_env->priv);
119 donotq_delete(iter_env->donotq);
120 if(iter_env->caps_white) {
121 traverse_postorder(iter_env->caps_white, caps_free, NULL);
122 free(iter_env->caps_white);
125 env->modinfo[id] = NULL;
128 /** new query for iterator */
130 iter_new(struct module_qstate* qstate, int id)
132 struct iter_qstate* iq = (struct iter_qstate*)regional_alloc(
133 qstate->region, sizeof(struct iter_qstate));
134 qstate->minfo[id] = iq;
137 memset(iq, 0, sizeof(*iq));
138 iq->state = INIT_REQUEST_STATE;
139 iq->final_state = FINISHED_STATE;
140 iq->an_prepend_list = NULL;
141 iq->an_prepend_last = NULL;
142 iq->ns_prepend_list = NULL;
143 iq->ns_prepend_last = NULL;
146 iq->num_target_queries = 0;
147 iq->num_current_queries = 0;
148 iq->query_restart_count = 0;
149 iq->referral_count = 0;
151 iq->ratelimit_ok = 0;
152 iq->target_count = NULL;
153 iq->wait_priming_stub = 0;
154 iq->refetch_glue = 0;
155 iq->dnssec_expected = 0;
156 iq->dnssec_lame_query = 0;
157 iq->chase_flags = qstate->query_flags;
158 /* Start with the (current) qname. */
159 iq->qchase = qstate->qinfo;
160 outbound_list_init(&iq->outlist);
161 iq->minimise_count = 0;
162 iq->minimise_timeout_count = 0;
163 if (qstate->env->cfg->qname_minimisation)
164 iq->minimisation_state = INIT_MINIMISE_STATE;
166 iq->minimisation_state = DONOT_MINIMISE_STATE;
168 memset(&iq->qinfo_out, 0, sizeof(struct query_info));
173 * Transition to the next state. This can be used to advance a currently
174 * processing event. It cannot be used to reactivate a forEvent.
176 * @param iq: iterator query state
177 * @param nextstate The state to transition to.
178 * @return true. This is so this can be called as the return value for the
179 * actual process*State() methods. (Transitioning to the next state
180 * implies further processing).
183 next_state(struct iter_qstate* iq, enum iter_state nextstate)
185 /* If transitioning to a "response" state, make sure that there is a
187 if(iter_state_is_responsestate(nextstate)) {
188 if(iq->response == NULL) {
189 log_err("transitioning to response state sans "
193 iq->state = nextstate;
198 * Transition an event to its final state. Final states always either return
199 * a result up the module chain, or reactivate a dependent event. Which
200 * final state to transition to is set in the module state for the event when
201 * it was created, and depends on the original purpose of the event.
203 * The response is stored in the qstate->buf buffer.
205 * @param iq: iterator query state
206 * @return false. This is so this method can be used as the return value for
207 * the processState methods. (Transitioning to the final state
210 final_state(struct iter_qstate* iq)
212 return next_state(iq, iq->final_state);
216 * Callback routine to handle errors in parent query states
217 * @param qstate: query state that failed.
218 * @param id: module id.
219 * @param super: super state.
222 error_supers(struct module_qstate* qstate, int id, struct module_qstate* super)
224 struct iter_qstate* super_iq = (struct iter_qstate*)super->minfo[id];
226 if(qstate->qinfo.qtype == LDNS_RR_TYPE_A ||
227 qstate->qinfo.qtype == LDNS_RR_TYPE_AAAA) {
228 /* mark address as failed. */
229 struct delegpt_ns* dpns = NULL;
230 super_iq->num_target_queries--;
232 dpns = delegpt_find_ns(super_iq->dp,
233 qstate->qinfo.qname, qstate->qinfo.qname_len);
236 /* this can happen, for eg. qname minimisation asked
237 * for an NXDOMAIN to be validated, and used qtype
238 * A for that, and the error of that, the name, is
239 * not listed in super_iq->dp */
240 verbose(VERB_ALGO, "subq error, but not interested");
241 log_query_info(VERB_ALGO, "superq", &super->qinfo);
244 /* see if the failure did get (parent-lame) info */
245 if(!cache_fill_missing(super->env, super_iq->qchase.qclass,
246 super->region, super_iq->dp))
247 log_err("out of memory adding missing");
249 dpns->resolved = 1; /* mark as failed */
251 if(qstate->qinfo.qtype == LDNS_RR_TYPE_NS) {
252 /* prime failed to get delegation */
255 /* evaluate targets again */
256 super_iq->state = QUERYTARGETS_STATE;
257 /* super becomes runnable, and will process this change */
261 * Return an error to the client
262 * @param qstate: our query state
263 * @param id: module id
264 * @param rcode: error code (DNS errcode).
265 * @return: 0 for use by caller, to make notation easy, like:
266 * return error_response(..).
269 error_response(struct module_qstate* qstate, int id, int rcode)
271 verbose(VERB_QUERY, "return error response %s",
272 sldns_lookup_by_id(sldns_rcodes, rcode)?
273 sldns_lookup_by_id(sldns_rcodes, rcode)->name:"??");
274 qstate->return_rcode = rcode;
275 qstate->return_msg = NULL;
276 qstate->ext_state[id] = module_finished;
281 * Return an error to the client and cache the error code in the
282 * message cache (so per qname, qtype, qclass).
283 * @param qstate: our query state
284 * @param id: module id
285 * @param rcode: error code (DNS errcode).
286 * @return: 0 for use by caller, to make notation easy, like:
287 * return error_response(..).
290 error_response_cache(struct module_qstate* qstate, int id, int rcode)
292 if(!qstate->no_cache_store) {
294 struct reply_info err;
295 if(qstate->prefetch_leeway > NORR_TTL) {
296 verbose(VERB_ALGO, "error response for prefetch in cache");
297 /* attempt to adjust the cache entry prefetch */
298 if(dns_cache_prefetch_adjust(qstate->env, &qstate->qinfo,
299 NORR_TTL, qstate->query_flags))
300 return error_response(qstate, id, rcode);
301 /* if that fails (not in cache), fall through to store err */
303 if(qstate->env->cfg->serve_expired) {
304 /* if serving expired contents, and such content is
305 * already available, don't overwrite this servfail */
306 struct msgreply_entry* msg;
307 if((msg=msg_cache_lookup(qstate->env,
308 qstate->qinfo.qname, qstate->qinfo.qname_len,
309 qstate->qinfo.qtype, qstate->qinfo.qclass,
310 qstate->query_flags, 0,
311 qstate->env->cfg->serve_expired_ttl_reset))
313 if(qstate->env->cfg->serve_expired_ttl_reset) {
314 struct reply_info* rep =
315 (struct reply_info*)msg->entry.data;
316 if(rep && *qstate->env->now +
317 qstate->env->cfg->serve_expired_ttl >
318 rep->serve_expired_ttl) {
319 rep->serve_expired_ttl =
321 qstate->env->cfg->serve_expired_ttl;
324 lock_rw_unlock(&msg->entry.lock);
325 return error_response(qstate, id, rcode);
327 /* serving expired contents, but nothing is cached
328 * at all, so the servfail cache entry is useful
329 * (stops waste of time on this servfail NORR_TTL) */
331 /* don't overwrite existing (non-expired) data in
332 * cache with a servfail */
333 struct msgreply_entry* msg;
334 if((msg=msg_cache_lookup(qstate->env,
335 qstate->qinfo.qname, qstate->qinfo.qname_len,
336 qstate->qinfo.qtype, qstate->qinfo.qclass,
337 qstate->query_flags, *qstate->env->now, 0))
339 struct reply_info* rep = (struct reply_info*)
341 if(FLAGS_GET_RCODE(rep->flags) ==
342 LDNS_RCODE_NOERROR ||
343 FLAGS_GET_RCODE(rep->flags) ==
344 LDNS_RCODE_NXDOMAIN) {
345 /* we have a good entry,
347 lock_rw_unlock(&msg->entry.lock);
348 return error_response(qstate, id, rcode);
350 lock_rw_unlock(&msg->entry.lock);
354 memset(&err, 0, sizeof(err));
355 err.flags = (uint16_t)(BIT_QR | BIT_RA);
356 FLAGS_SET_RCODE(err.flags, rcode);
359 err.prefetch_ttl = PREFETCH_TTL_CALC(err.ttl);
360 err.serve_expired_ttl = NORR_TTL;
361 /* do not waste time trying to validate this servfail */
362 err.security = sec_status_indeterminate;
363 verbose(VERB_ALGO, "store error response in message cache");
364 iter_dns_store(qstate->env, &qstate->qinfo, &err, 0, 0, 0, NULL,
365 qstate->query_flags);
367 return error_response(qstate, id, rcode);
370 /** check if prepend item is duplicate item */
372 prepend_is_duplicate(struct ub_packed_rrset_key** sets, size_t to,
373 struct ub_packed_rrset_key* dup)
376 for(i=0; i<to; i++) {
377 if(sets[i]->rk.type == dup->rk.type &&
378 sets[i]->rk.rrset_class == dup->rk.rrset_class &&
379 sets[i]->rk.dname_len == dup->rk.dname_len &&
380 query_dname_compare(sets[i]->rk.dname, dup->rk.dname)
387 /** prepend the prepend list in the answer and authority section of dns_msg */
389 iter_prepend(struct iter_qstate* iq, struct dns_msg* msg,
390 struct regional* region)
392 struct iter_prep_list* p;
393 struct ub_packed_rrset_key** sets;
394 size_t num_an = 0, num_ns = 0;;
395 for(p = iq->an_prepend_list; p; p = p->next)
397 for(p = iq->ns_prepend_list; p; p = p->next)
399 if(num_an + num_ns == 0)
401 verbose(VERB_ALGO, "prepending %d rrsets", (int)num_an + (int)num_ns);
402 if(num_an > RR_COUNT_MAX || num_ns > RR_COUNT_MAX ||
403 msg->rep->rrset_count > RR_COUNT_MAX) return 0; /* overflow */
404 sets = regional_alloc(region, (num_an+num_ns+msg->rep->rrset_count) *
405 sizeof(struct ub_packed_rrset_key*));
410 for(p = iq->an_prepend_list; p; p = p->next) {
411 sets[num_an++] = p->rrset;
413 memcpy(sets+num_an, msg->rep->rrsets, msg->rep->an_numrrsets *
414 sizeof(struct ub_packed_rrset_key*));
417 for(p = iq->ns_prepend_list; p; p = p->next) {
418 if(prepend_is_duplicate(sets+msg->rep->an_numrrsets+num_an,
419 num_ns, p->rrset) || prepend_is_duplicate(
420 msg->rep->rrsets+msg->rep->an_numrrsets,
421 msg->rep->ns_numrrsets, p->rrset))
423 sets[msg->rep->an_numrrsets + num_an + num_ns++] = p->rrset;
425 memcpy(sets + num_an + msg->rep->an_numrrsets + num_ns,
426 msg->rep->rrsets + msg->rep->an_numrrsets,
427 (msg->rep->ns_numrrsets + msg->rep->ar_numrrsets) *
428 sizeof(struct ub_packed_rrset_key*));
430 /* NXDOMAIN rcode can stay if we prepended DNAME/CNAMEs, because
431 * this is what recursors should give. */
432 msg->rep->rrset_count += num_an + num_ns;
433 msg->rep->an_numrrsets += num_an;
434 msg->rep->ns_numrrsets += num_ns;
435 msg->rep->rrsets = sets;
440 * Find rrset in ANSWER prepend list.
441 * to avoid duplicate DNAMEs when a DNAME is traversed twice.
442 * @param iq: iterator query state.
443 * @param rrset: rrset to add.
444 * @return false if not found
447 iter_find_rrset_in_prepend_answer(struct iter_qstate* iq,
448 struct ub_packed_rrset_key* rrset)
450 struct iter_prep_list* p = iq->an_prepend_list;
452 if(ub_rrset_compare(p->rrset, rrset) == 0 &&
453 rrsetdata_equal((struct packed_rrset_data*)p->rrset
454 ->entry.data, (struct packed_rrset_data*)rrset
463 * Add rrset to ANSWER prepend list
464 * @param qstate: query state.
465 * @param iq: iterator query state.
466 * @param rrset: rrset to add.
467 * @return false on failure (malloc).
470 iter_add_prepend_answer(struct module_qstate* qstate, struct iter_qstate* iq,
471 struct ub_packed_rrset_key* rrset)
473 struct iter_prep_list* p = (struct iter_prep_list*)regional_alloc(
474 qstate->region, sizeof(struct iter_prep_list));
480 if(iq->an_prepend_last)
481 iq->an_prepend_last->next = p;
482 else iq->an_prepend_list = p;
483 iq->an_prepend_last = p;
488 * Add rrset to AUTHORITY prepend list
489 * @param qstate: query state.
490 * @param iq: iterator query state.
491 * @param rrset: rrset to add.
492 * @return false on failure (malloc).
495 iter_add_prepend_auth(struct module_qstate* qstate, struct iter_qstate* iq,
496 struct ub_packed_rrset_key* rrset)
498 struct iter_prep_list* p = (struct iter_prep_list*)regional_alloc(
499 qstate->region, sizeof(struct iter_prep_list));
505 if(iq->ns_prepend_last)
506 iq->ns_prepend_last->next = p;
507 else iq->ns_prepend_list = p;
508 iq->ns_prepend_last = p;
513 * Given a CNAME response (defined as a response containing a CNAME or DNAME
514 * that does not answer the request), process the response, modifying the
515 * state as necessary. This follows the CNAME/DNAME chain and returns the
518 * sets the new query name, after following the CNAME/DNAME chain.
519 * @param qstate: query state.
520 * @param iq: iterator query state.
521 * @param msg: the response.
522 * @param mname: returned target new query name.
523 * @param mname_len: length of mname.
524 * @return false on (malloc) error.
527 handle_cname_response(struct module_qstate* qstate, struct iter_qstate* iq,
528 struct dns_msg* msg, uint8_t** mname, size_t* mname_len)
531 /* Start with the (current) qname. */
532 *mname = iq->qchase.qname;
533 *mname_len = iq->qchase.qname_len;
535 /* Iterate over the ANSWER rrsets in order, looking for CNAMEs and
537 for(i=0; i<msg->rep->an_numrrsets; i++) {
538 struct ub_packed_rrset_key* r = msg->rep->rrsets[i];
539 /* If there is a (relevant) DNAME, add it to the list.
540 * We always expect there to be CNAME that was generated
541 * by this DNAME following, so we don't process the DNAME
543 if(ntohs(r->rk.type) == LDNS_RR_TYPE_DNAME &&
544 dname_strict_subdomain_c(*mname, r->rk.dname) &&
545 !iter_find_rrset_in_prepend_answer(iq, r)) {
546 if(!iter_add_prepend_answer(qstate, iq, r))
551 if(ntohs(r->rk.type) == LDNS_RR_TYPE_CNAME &&
552 query_dname_compare(*mname, r->rk.dname) == 0 &&
553 !iter_find_rrset_in_prepend_answer(iq, r)) {
554 /* Add this relevant CNAME rrset to the prepend list.*/
555 if(!iter_add_prepend_answer(qstate, iq, r))
557 get_cname_target(r, mname, mname_len);
560 /* Other rrsets in the section are ignored. */
562 /* add authority rrsets to authority prepend, for wildcarded CNAMEs */
563 for(i=msg->rep->an_numrrsets; i<msg->rep->an_numrrsets +
564 msg->rep->ns_numrrsets; i++) {
565 struct ub_packed_rrset_key* r = msg->rep->rrsets[i];
566 /* only add NSEC/NSEC3, as they may be needed for validation */
567 if(ntohs(r->rk.type) == LDNS_RR_TYPE_NSEC ||
568 ntohs(r->rk.type) == LDNS_RR_TYPE_NSEC3) {
569 if(!iter_add_prepend_auth(qstate, iq, r))
576 /** see if last resort is possible - does config allow queries to parent */
578 can_have_last_resort(struct module_env* env, uint8_t* nm, size_t nmlen,
579 uint16_t qclass, struct delegpt** retdp)
581 struct delegpt* fwddp;
582 struct iter_hints_stub* stub;
583 int labs = dname_count_labels(nm);
584 /* do not process a last resort (the parent side) if a stub
585 * or forward is configured, because we do not want to go 'above'
586 * the configured servers */
587 if(!dname_is_root(nm) && (stub = (struct iter_hints_stub*)
588 name_tree_find(&env->hints->tree, nm, nmlen, labs, qclass)) &&
589 /* has_parent side is turned off for stub_first, where we
590 * are allowed to go to the parent */
591 stub->dp->has_parent_side_NS) {
592 if(retdp) *retdp = stub->dp;
595 if((fwddp = forwards_find(env->fwds, nm, qclass)) &&
596 /* has_parent_side is turned off for forward_first, where
597 * we are allowed to go to the parent */
598 fwddp->has_parent_side_NS) {
599 if(retdp) *retdp = fwddp;
605 /** see if target name is caps-for-id whitelisted */
607 is_caps_whitelisted(struct iter_env* ie, struct iter_qstate* iq)
609 if(!ie->caps_white) return 0; /* no whitelist, or no capsforid */
610 return name_tree_lookup(ie->caps_white, iq->qchase.qname,
611 iq->qchase.qname_len, dname_count_labels(iq->qchase.qname),
612 iq->qchase.qclass) != NULL;
615 /** create target count structure for this query */
617 target_count_create(struct iter_qstate* iq)
619 if(!iq->target_count) {
620 iq->target_count = (int*)calloc(2, sizeof(int));
621 /* if calloc fails we simply do not track this number */
623 iq->target_count[0] = 1;
628 target_count_increase(struct iter_qstate* iq, int num)
630 target_count_create(iq);
632 iq->target_count[1] += num;
636 * Generate a subrequest.
637 * Generate a local request event. Local events are tied to this module, and
638 * have a corresponding (first tier) event that is waiting for this event to
639 * resolve to continue.
641 * @param qname The query name for this request.
642 * @param qnamelen length of qname
643 * @param qtype The query type for this request.
644 * @param qclass The query class for this request.
645 * @param qstate The event that is generating this event.
646 * @param id: module id.
647 * @param iq: The iterator state that is generating this event.
648 * @param initial_state The initial response state (normally this
649 * is QUERY_RESP_STATE, unless it is known that the request won't
650 * need iterative processing
651 * @param finalstate The final state for the response to this request.
652 * @param subq_ret: if newly allocated, the subquerystate, or NULL if it does
653 * not need initialisation.
654 * @param v: if true, validation is done on the subquery.
655 * @return false on error (malloc).
658 generate_sub_request(uint8_t* qname, size_t qnamelen, uint16_t qtype,
659 uint16_t qclass, struct module_qstate* qstate, int id,
660 struct iter_qstate* iq, enum iter_state initial_state,
661 enum iter_state finalstate, struct module_qstate** subq_ret, int v)
663 struct module_qstate* subq = NULL;
664 struct iter_qstate* subiq = NULL;
665 uint16_t qflags = 0; /* OPCODE QUERY, no flags */
666 struct query_info qinf;
667 int prime = (finalstate == PRIME_RESP_STATE)?1:0;
670 qinf.qname_len = qnamelen;
672 qinf.qclass = qclass;
673 qinf.local_alias = NULL;
675 /* RD should be set only when sending the query back through the INIT
677 if(initial_state == INIT_REQUEST_STATE)
679 /* We set the CD flag so we can send this through the "head" of
680 * the resolution chain, which might have a validator. We are
681 * uninterested in validating things not on the direct resolution
688 /* attach subquery, lookup existing or make a new one */
689 fptr_ok(fptr_whitelist_modenv_attach_sub(qstate->env->attach_sub));
690 if(!(*qstate->env->attach_sub)(qstate, &qinf, qflags, prime, valrec,
696 /* initialise the new subquery */
698 subq->ext_state[id] = module_state_initial;
699 subq->minfo[id] = regional_alloc(subq->region,
700 sizeof(struct iter_qstate));
701 if(!subq->minfo[id]) {
702 log_err("init subq: out of memory");
703 fptr_ok(fptr_whitelist_modenv_kill_sub(
704 qstate->env->kill_sub));
705 (*qstate->env->kill_sub)(subq);
708 subiq = (struct iter_qstate*)subq->minfo[id];
709 memset(subiq, 0, sizeof(*subiq));
710 subiq->num_target_queries = 0;
711 target_count_create(iq);
712 subiq->target_count = iq->target_count;
714 iq->target_count[0] ++; /* extra reference */
715 subiq->num_current_queries = 0;
716 subiq->depth = iq->depth+1;
717 outbound_list_init(&subiq->outlist);
718 subiq->state = initial_state;
719 subiq->final_state = finalstate;
720 subiq->qchase = subq->qinfo;
721 subiq->chase_flags = subq->query_flags;
722 subiq->refetch_glue = 0;
723 if(qstate->env->cfg->qname_minimisation)
724 subiq->minimisation_state = INIT_MINIMISE_STATE;
726 subiq->minimisation_state = DONOT_MINIMISE_STATE;
727 memset(&subiq->qinfo_out, 0, sizeof(struct query_info));
733 * Generate and send a root priming request.
734 * @param qstate: the qtstate that triggered the need to prime.
735 * @param iq: iterator query state.
736 * @param id: module id.
737 * @param qclass: the class to prime.
738 * @return 0 on failure
741 prime_root(struct module_qstate* qstate, struct iter_qstate* iq, int id,
745 struct module_qstate* subq;
746 verbose(VERB_DETAIL, "priming . %s NS",
747 sldns_lookup_by_id(sldns_rr_classes, (int)qclass)?
748 sldns_lookup_by_id(sldns_rr_classes, (int)qclass)->name:"??");
749 dp = hints_lookup_root(qstate->env->hints, qclass);
751 verbose(VERB_ALGO, "Cannot prime due to lack of hints");
754 /* Priming requests start at the QUERYTARGETS state, skipping
755 * the normal INIT state logic (which would cause an infloop). */
756 if(!generate_sub_request((uint8_t*)"\000", 1, LDNS_RR_TYPE_NS,
757 qclass, qstate, id, iq, QUERYTARGETS_STATE, PRIME_RESP_STATE,
759 verbose(VERB_ALGO, "could not prime root");
763 struct iter_qstate* subiq =
764 (struct iter_qstate*)subq->minfo[id];
765 /* Set the initial delegation point to the hint.
766 * copy dp, it is now part of the root prime query.
767 * dp was part of in the fixed hints structure. */
768 subiq->dp = delegpt_copy(dp, subq->region);
770 log_err("out of memory priming root, copydp");
771 fptr_ok(fptr_whitelist_modenv_kill_sub(
772 qstate->env->kill_sub));
773 (*qstate->env->kill_sub)(subq);
776 /* there should not be any target queries. */
777 subiq->num_target_queries = 0;
778 subiq->dnssec_expected = iter_indicates_dnssec(
779 qstate->env, subiq->dp, NULL, subq->qinfo.qclass);
782 /* this module stops, our submodule starts, and does the query. */
783 qstate->ext_state[id] = module_wait_subquery;
788 * Generate and process a stub priming request. This method tests for the
789 * need to prime a stub zone, so it is safe to call for every request.
791 * @param qstate: the qtstate that triggered the need to prime.
792 * @param iq: iterator query state.
793 * @param id: module id.
794 * @param qname: request name.
795 * @param qclass: request class.
796 * @return true if a priming subrequest was made, false if not. The will only
797 * issue a priming request if it detects an unprimed stub.
798 * Uses value of 2 to signal during stub-prime in root-prime situation
799 * that a noprime-stub is available and resolution can continue.
802 prime_stub(struct module_qstate* qstate, struct iter_qstate* iq, int id,
803 uint8_t* qname, uint16_t qclass)
805 /* Lookup the stub hint. This will return null if the stub doesn't
806 * need to be re-primed. */
807 struct iter_hints_stub* stub;
808 struct delegpt* stub_dp;
809 struct module_qstate* subq;
812 stub = hints_lookup_stub(qstate->env->hints, qname, qclass, iq->dp);
813 /* The stub (if there is one) does not need priming. */
817 /* if we have an auth_zone dp, and stub is equal, don't prime stub
818 * yet, unless we want to fallback and avoid the auth_zone */
819 if(!iq->auth_zone_avoid && iq->dp && iq->dp->auth_dp &&
820 query_dname_compare(iq->dp->name, stub_dp->name) == 0)
823 /* is it a noprime stub (always use) */
826 if(iq->dp == NULL) r = 2;
827 /* copy the dp out of the fixed hints structure, so that
828 * it can be changed when servicing this query */
829 iq->dp = delegpt_copy(stub_dp, qstate->region);
831 log_err("out of memory priming stub");
832 errinf(qstate, "malloc failure, priming stub");
833 (void)error_response(qstate, id, LDNS_RCODE_SERVFAIL);
834 return 1; /* return 1 to make module stop, with error */
836 log_nametypeclass(VERB_DETAIL, "use stub", stub_dp->name,
837 LDNS_RR_TYPE_NS, qclass);
841 /* Otherwise, we need to (re)prime the stub. */
842 log_nametypeclass(VERB_DETAIL, "priming stub", stub_dp->name,
843 LDNS_RR_TYPE_NS, qclass);
845 /* Stub priming events start at the QUERYTARGETS state to avoid the
846 * redundant INIT state processing. */
847 if(!generate_sub_request(stub_dp->name, stub_dp->namelen,
848 LDNS_RR_TYPE_NS, qclass, qstate, id, iq,
849 QUERYTARGETS_STATE, PRIME_RESP_STATE, &subq, 0)) {
850 verbose(VERB_ALGO, "could not prime stub");
851 errinf(qstate, "could not generate lookup for stub prime");
852 (void)error_response(qstate, id, LDNS_RCODE_SERVFAIL);
853 return 1; /* return 1 to make module stop, with error */
856 struct iter_qstate* subiq =
857 (struct iter_qstate*)subq->minfo[id];
859 /* Set the initial delegation point to the hint. */
860 /* make copy to avoid use of stub dp by different qs/threads */
861 subiq->dp = delegpt_copy(stub_dp, subq->region);
863 log_err("out of memory priming stub, copydp");
864 fptr_ok(fptr_whitelist_modenv_kill_sub(
865 qstate->env->kill_sub));
866 (*qstate->env->kill_sub)(subq);
867 errinf(qstate, "malloc failure, in stub prime");
868 (void)error_response(qstate, id, LDNS_RCODE_SERVFAIL);
869 return 1; /* return 1 to make module stop, with error */
871 /* there should not be any target queries -- although there
872 * wouldn't be anyway, since stub hints never have
873 * missing targets. */
874 subiq->num_target_queries = 0;
875 subiq->wait_priming_stub = 1;
876 subiq->dnssec_expected = iter_indicates_dnssec(
877 qstate->env, subiq->dp, NULL, subq->qinfo.qclass);
880 /* this module stops, our submodule starts, and does the query. */
881 qstate->ext_state[id] = module_wait_subquery;
886 * Generate a delegation point for an auth zone (unless cached dp is better)
887 * false on alloc failure.
890 auth_zone_delegpt(struct module_qstate* qstate, struct iter_qstate* iq,
891 uint8_t* delname, size_t delnamelen)
894 if(iq->auth_zone_avoid)
897 delname = iq->qchase.qname;
898 delnamelen = iq->qchase.qname_len;
900 lock_rw_rdlock(&qstate->env->auth_zones->lock);
901 z = auth_zones_find_zone(qstate->env->auth_zones, delname, delnamelen,
902 qstate->qinfo.qclass);
904 lock_rw_unlock(&qstate->env->auth_zones->lock);
907 lock_rw_rdlock(&z->lock);
908 lock_rw_unlock(&qstate->env->auth_zones->lock);
909 if(z->for_upstream) {
910 if(iq->dp && query_dname_compare(z->name, iq->dp->name) == 0
911 && iq->dp->auth_dp && qstate->blacklist &&
912 z->fallback_enabled) {
913 /* cache is blacklisted and fallback, and we
914 * already have an auth_zone dp */
915 if(verbosity>=VERB_ALGO) {
917 dname_str(z->name, buf);
918 verbose(VERB_ALGO, "auth_zone %s "
919 "fallback because cache blacklisted",
922 lock_rw_unlock(&z->lock);
926 if(iq->dp==NULL || dname_subdomain_c(z->name, iq->dp->name)) {
928 if(qstate->blacklist && z->fallback_enabled) {
929 /* cache is blacklisted because of a DNSSEC
930 * validation failure, and the zone allows
931 * fallback to the internet, query there. */
932 if(verbosity>=VERB_ALGO) {
934 dname_str(z->name, buf);
935 verbose(VERB_ALGO, "auth_zone %s "
936 "fallback because cache blacklisted",
939 lock_rw_unlock(&z->lock);
942 dp = (struct delegpt*)regional_alloc_zero(
943 qstate->region, sizeof(*dp));
945 log_err("alloc failure");
946 if(z->fallback_enabled) {
947 lock_rw_unlock(&z->lock);
948 return 1; /* just fallback */
950 lock_rw_unlock(&z->lock);
951 errinf(qstate, "malloc failure");
954 dp->name = regional_alloc_init(qstate->region,
955 z->name, z->namelen);
957 log_err("alloc failure");
958 if(z->fallback_enabled) {
959 lock_rw_unlock(&z->lock);
960 return 1; /* just fallback */
962 lock_rw_unlock(&z->lock);
963 errinf(qstate, "malloc failure");
966 dp->namelen = z->namelen;
967 dp->namelabs = z->namelabs;
973 lock_rw_unlock(&z->lock);
978 * Generate A and AAAA checks for glue that is in-zone for the referral
979 * we just got to obtain authoritative information on the addresses.
981 * @param qstate: the qtstate that triggered the need to prime.
982 * @param iq: iterator query state.
983 * @param id: module id.
986 generate_a_aaaa_check(struct module_qstate* qstate, struct iter_qstate* iq,
989 struct iter_env* ie = (struct iter_env*)qstate->env->modinfo[id];
990 struct module_qstate* subq;
992 struct reply_info* rep = iq->response->rep;
993 struct ub_packed_rrset_key* s;
996 if(iq->depth == ie->max_dependency_depth)
998 /* walk through additional, and check if in-zone,
999 * only relevant A, AAAA are left after scrub anyway */
1000 for(i=rep->an_numrrsets+rep->ns_numrrsets; i<rep->rrset_count; i++) {
1002 /* check *ALL* addresses that are transmitted in additional*/
1003 /* is it an address ? */
1004 if( !(ntohs(s->rk.type)==LDNS_RR_TYPE_A ||
1005 ntohs(s->rk.type)==LDNS_RR_TYPE_AAAA)) {
1008 /* is this query the same as the A/AAAA check for it */
1009 if(qstate->qinfo.qtype == ntohs(s->rk.type) &&
1010 qstate->qinfo.qclass == ntohs(s->rk.rrset_class) &&
1011 query_dname_compare(qstate->qinfo.qname,
1013 (qstate->query_flags&BIT_RD) &&
1014 !(qstate->query_flags&BIT_CD))
1017 /* generate subrequest for it */
1018 log_nametypeclass(VERB_ALGO, "schedule addr fetch",
1019 s->rk.dname, ntohs(s->rk.type),
1020 ntohs(s->rk.rrset_class));
1021 if(!generate_sub_request(s->rk.dname, s->rk.dname_len,
1022 ntohs(s->rk.type), ntohs(s->rk.rrset_class),
1024 INIT_REQUEST_STATE, FINISHED_STATE, &subq, 1)) {
1025 verbose(VERB_ALGO, "could not generate addr check");
1028 /* ignore subq - not need for more init */
1033 * Generate a NS check request to obtain authoritative information
1036 * @param qstate: the qtstate that triggered the need to prime.
1037 * @param iq: iterator query state.
1038 * @param id: module id.
1041 generate_ns_check(struct module_qstate* qstate, struct iter_qstate* iq, int id)
1043 struct iter_env* ie = (struct iter_env*)qstate->env->modinfo[id];
1044 struct module_qstate* subq;
1047 if(iq->depth == ie->max_dependency_depth)
1049 if(!can_have_last_resort(qstate->env, iq->dp->name, iq->dp->namelen,
1050 iq->qchase.qclass, NULL))
1052 /* is this query the same as the nscheck? */
1053 if(qstate->qinfo.qtype == LDNS_RR_TYPE_NS &&
1054 query_dname_compare(iq->dp->name, qstate->qinfo.qname)==0 &&
1055 (qstate->query_flags&BIT_RD) && !(qstate->query_flags&BIT_CD)){
1056 /* spawn off A, AAAA queries for in-zone glue to check */
1057 generate_a_aaaa_check(qstate, iq, id);
1060 /* no need to get the NS record for DS, it is above the zonecut */
1061 if(qstate->qinfo.qtype == LDNS_RR_TYPE_DS)
1064 log_nametypeclass(VERB_ALGO, "schedule ns fetch",
1065 iq->dp->name, LDNS_RR_TYPE_NS, iq->qchase.qclass);
1066 if(!generate_sub_request(iq->dp->name, iq->dp->namelen,
1067 LDNS_RR_TYPE_NS, iq->qchase.qclass, qstate, id, iq,
1068 INIT_REQUEST_STATE, FINISHED_STATE, &subq, 1)) {
1069 verbose(VERB_ALGO, "could not generate ns check");
1073 struct iter_qstate* subiq =
1074 (struct iter_qstate*)subq->minfo[id];
1076 /* make copy to avoid use of stub dp by different qs/threads */
1077 /* refetch glue to start higher up the tree */
1078 subiq->refetch_glue = 1;
1079 subiq->dp = delegpt_copy(iq->dp, subq->region);
1081 log_err("out of memory generating ns check, copydp");
1082 fptr_ok(fptr_whitelist_modenv_kill_sub(
1083 qstate->env->kill_sub));
1084 (*qstate->env->kill_sub)(subq);
1091 * Generate a DNSKEY prefetch query to get the DNSKEY for the DS record we
1092 * just got in a referral (where we have dnssec_expected, thus have trust
1093 * anchors above it). Note that right after calling this routine the
1094 * iterator detached subqueries (because of following the referral), and thus
1095 * the DNSKEY query becomes detached, its return stored in the cache for
1096 * later lookup by the validator. This cache lookup by the validator avoids
1097 * the roundtrip incurred by the DNSKEY query. The DNSKEY query is now
1098 * performed at about the same time the original query is sent to the domain,
1099 * thus the two answers are likely to be returned at about the same time,
1100 * saving a roundtrip from the validated lookup.
1102 * @param qstate: the qtstate that triggered the need to prime.
1103 * @param iq: iterator query state.
1104 * @param id: module id.
1107 generate_dnskey_prefetch(struct module_qstate* qstate,
1108 struct iter_qstate* iq, int id)
1110 struct module_qstate* subq;
1113 /* is this query the same as the prefetch? */
1114 if(qstate->qinfo.qtype == LDNS_RR_TYPE_DNSKEY &&
1115 query_dname_compare(iq->dp->name, qstate->qinfo.qname)==0 &&
1116 (qstate->query_flags&BIT_RD) && !(qstate->query_flags&BIT_CD)){
1120 /* if the DNSKEY is in the cache this lookup will stop quickly */
1121 log_nametypeclass(VERB_ALGO, "schedule dnskey prefetch",
1122 iq->dp->name, LDNS_RR_TYPE_DNSKEY, iq->qchase.qclass);
1123 if(!generate_sub_request(iq->dp->name, iq->dp->namelen,
1124 LDNS_RR_TYPE_DNSKEY, iq->qchase.qclass, qstate, id, iq,
1125 INIT_REQUEST_STATE, FINISHED_STATE, &subq, 0)) {
1126 /* we'll be slower, but it'll work */
1127 verbose(VERB_ALGO, "could not generate dnskey prefetch");
1131 struct iter_qstate* subiq =
1132 (struct iter_qstate*)subq->minfo[id];
1133 /* this qstate has the right delegation for the dnskey lookup*/
1134 /* make copy to avoid use of stub dp by different qs/threads */
1135 subiq->dp = delegpt_copy(iq->dp, subq->region);
1136 /* if !subiq->dp, it'll start from the cache, no problem */
1141 * See if the query needs forwarding.
1143 * @param qstate: query state.
1144 * @param iq: iterator query state.
1145 * @return true if the request is forwarded, false if not.
1146 * If returns true but, iq->dp is NULL then a malloc failure occurred.
1149 forward_request(struct module_qstate* qstate, struct iter_qstate* iq)
1152 uint8_t* delname = iq->qchase.qname;
1153 size_t delnamelen = iq->qchase.qname_len;
1154 if(iq->refetch_glue && iq->dp) {
1155 delname = iq->dp->name;
1156 delnamelen = iq->dp->namelen;
1158 /* strip one label off of DS query to lookup higher for it */
1159 if( (iq->qchase.qtype == LDNS_RR_TYPE_DS || iq->refetch_glue)
1160 && !dname_is_root(iq->qchase.qname))
1161 dname_remove_label(&delname, &delnamelen);
1162 dp = forwards_lookup(qstate->env->fwds, delname, iq->qchase.qclass);
1165 /* send recursion desired to forward addr */
1166 iq->chase_flags |= BIT_RD;
1167 iq->dp = delegpt_copy(dp, qstate->region);
1168 /* iq->dp checked by caller */
1169 verbose(VERB_ALGO, "forwarding request");
1174 * Process the initial part of the request handling. This state roughly
1175 * corresponds to resolver algorithms steps 1 (find answer in cache) and 2
1176 * (find the best servers to ask).
1178 * Note that all requests start here, and query restarts revisit this state.
1180 * This state either generates: 1) a response, from cache or error, 2) a
1181 * priming event, or 3) forwards the request to the next state (init2,
1184 * @param qstate: query state.
1185 * @param iq: iterator query state.
1186 * @param ie: iterator shared global environment.
1187 * @param id: module id.
1188 * @return true if the event needs more request processing immediately,
1192 processInitRequest(struct module_qstate* qstate, struct iter_qstate* iq,
1193 struct iter_env* ie, int id)
1197 struct dns_msg* msg = NULL;
1199 log_query_info(VERB_DETAIL, "resolving", &qstate->qinfo);
1202 /* We enforce a maximum number of query restarts. This is primarily a
1203 * cheap way to prevent CNAME loops. */
1204 if(iq->query_restart_count > MAX_RESTART_COUNT) {
1205 verbose(VERB_QUERY, "request has exceeded the maximum number"
1206 " of query restarts with %d", iq->query_restart_count);
1207 errinf(qstate, "request has exceeded the maximum number "
1208 "restarts (eg. indirections)");
1209 if(iq->qchase.qname)
1210 errinf_dname(qstate, "stop at", iq->qchase.qname);
1211 return error_response(qstate, id, LDNS_RCODE_SERVFAIL);
1214 /* We enforce a maximum recursion/dependency depth -- in general,
1215 * this is unnecessary for dependency loops (although it will
1216 * catch those), but it provides a sensible limit to the amount
1217 * of work required to answer a given query. */
1218 verbose(VERB_ALGO, "request has dependency depth of %d", iq->depth);
1219 if(iq->depth > ie->max_dependency_depth) {
1220 verbose(VERB_QUERY, "request has exceeded the maximum "
1221 "dependency depth with depth of %d", iq->depth);
1222 errinf(qstate, "request has exceeded the maximum dependency "
1223 "depth (eg. nameserver lookup recursion)");
1224 return error_response(qstate, id, LDNS_RCODE_SERVFAIL);
1227 /* If the request is qclass=ANY, setup to generate each class */
1228 if(qstate->qinfo.qclass == LDNS_RR_CLASS_ANY) {
1229 iq->qchase.qclass = 0;
1230 return next_state(iq, COLLECT_CLASS_STATE);
1234 * If we are restricted by a forward-zone or a stub-zone, we
1235 * can't re-fetch glue for this delegation point.
1236 * we won’t try to re-fetch glue if the iq->dp is null.
1238 if (iq->refetch_glue &&
1240 !can_have_last_resort(qstate->env, iq->dp->name,
1241 iq->dp->namelen, iq->qchase.qclass, NULL)) {
1242 iq->refetch_glue = 0;
1245 /* Resolver Algorithm Step 1 -- Look for the answer in local data. */
1247 /* This either results in a query restart (CNAME cache response), a
1248 * terminating response (ANSWER), or a cache miss (null). */
1250 if (iter_stub_fwd_no_cache(qstate, &iq->qchase)) {
1251 /* Asked to not query cache. */
1252 verbose(VERB_ALGO, "no-cache set, going to the network");
1253 qstate->no_cache_lookup = 1;
1254 qstate->no_cache_store = 1;
1256 } else if(qstate->blacklist) {
1257 /* if cache, or anything else, was blacklisted then
1258 * getting older results from cache is a bad idea, no cache */
1259 verbose(VERB_ALGO, "cache blacklisted, going to the network");
1261 } else if(!qstate->no_cache_lookup) {
1262 msg = dns_cache_lookup(qstate->env, iq->qchase.qname,
1263 iq->qchase.qname_len, iq->qchase.qtype,
1264 iq->qchase.qclass, qstate->query_flags,
1265 qstate->region, qstate->env->scratch, 0);
1266 if(!msg && qstate->env->neg_cache &&
1267 iter_qname_indicates_dnssec(qstate->env, &iq->qchase)) {
1268 /* lookup in negative cache; may result in
1269 * NOERROR/NODATA or NXDOMAIN answers that need validation */
1270 msg = val_neg_getmsg(qstate->env->neg_cache, &iq->qchase,
1271 qstate->region, qstate->env->rrset_cache,
1272 qstate->env->scratch_buffer,
1273 *qstate->env->now, 1/*add SOA*/, NULL,
1276 /* item taken from cache does not match our query name, thus
1277 * security needs to be re-examined later */
1278 if(msg && query_dname_compare(qstate->qinfo.qname,
1279 iq->qchase.qname) != 0)
1280 msg->rep->security = sec_status_unchecked;
1283 /* handle positive cache response */
1284 enum response_type type = response_type_from_cache(msg,
1286 if(verbosity >= VERB_ALGO) {
1287 log_dns_msg("msg from cache lookup", &msg->qinfo,
1289 verbose(VERB_ALGO, "msg ttl is %d, prefetch ttl %d",
1291 (int)msg->rep->prefetch_ttl);
1294 if(type == RESPONSE_TYPE_CNAME) {
1297 verbose(VERB_ALGO, "returning CNAME response from "
1299 if(!handle_cname_response(qstate, iq, msg,
1301 errinf(qstate, "failed to prepend CNAME "
1302 "components, malloc failure");
1303 return error_response(qstate, id,
1304 LDNS_RCODE_SERVFAIL);
1306 iq->qchase.qname = sname;
1307 iq->qchase.qname_len = slen;
1308 /* This *is* a query restart, even if it is a cheap
1311 iq->refetch_glue = 0;
1312 iq->query_restart_count++;
1314 sock_list_insert(&qstate->reply_origin, NULL, 0, qstate->region);
1315 if(qstate->env->cfg->qname_minimisation)
1316 iq->minimisation_state = INIT_MINIMISE_STATE;
1317 return next_state(iq, INIT_REQUEST_STATE);
1320 /* if from cache, NULL, else insert 'cache IP' len=0 */
1321 if(qstate->reply_origin)
1322 sock_list_insert(&qstate->reply_origin, NULL, 0, qstate->region);
1323 if(FLAGS_GET_RCODE(msg->rep->flags) == LDNS_RCODE_SERVFAIL)
1324 errinf(qstate, "SERVFAIL in cache");
1325 /* it is an answer, response, to final state */
1326 verbose(VERB_ALGO, "returning answer from cache.");
1328 return final_state(iq);
1331 /* attempt to forward the request */
1332 if(forward_request(qstate, iq))
1335 log_err("alloc failure for forward dp");
1336 errinf(qstate, "malloc failure for forward zone");
1337 return error_response(qstate, id, LDNS_RCODE_SERVFAIL);
1339 iq->refetch_glue = 0;
1340 iq->minimisation_state = DONOT_MINIMISE_STATE;
1341 /* the request has been forwarded.
1342 * forwarded requests need to be immediately sent to the
1343 * next state, QUERYTARGETS. */
1344 return next_state(iq, QUERYTARGETS_STATE);
1347 /* Resolver Algorithm Step 2 -- find the "best" servers. */
1349 /* first, adjust for DS queries. To avoid the grandparent problem,
1350 * we just look for the closest set of server to the parent of qname.
1351 * When re-fetching glue we also need to ask the parent.
1353 if(iq->refetch_glue) {
1355 log_err("internal or malloc fail: no dp for refetch");
1356 errinf(qstate, "malloc failure, for delegation info");
1357 return error_response(qstate, id, LDNS_RCODE_SERVFAIL);
1359 delname = iq->dp->name;
1360 delnamelen = iq->dp->namelen;
1362 delname = iq->qchase.qname;
1363 delnamelen = iq->qchase.qname_len;
1365 if(iq->qchase.qtype == LDNS_RR_TYPE_DS || iq->refetch_glue ||
1366 (iq->qchase.qtype == LDNS_RR_TYPE_NS && qstate->prefetch_leeway
1367 && can_have_last_resort(qstate->env, delname, delnamelen, iq->qchase.qclass, NULL))) {
1368 /* remove first label from delname, root goes to hints,
1369 * but only to fetch glue, not for qtype=DS. */
1370 /* also when prefetching an NS record, fetch it again from
1371 * its parent, just as if it expired, so that you do not
1372 * get stuck on an older nameserver that gives old NSrecords */
1373 if(dname_is_root(delname) && (iq->refetch_glue ||
1374 (iq->qchase.qtype == LDNS_RR_TYPE_NS &&
1375 qstate->prefetch_leeway)))
1376 delname = NULL; /* go to root priming */
1377 else dname_remove_label(&delname, &delnamelen);
1379 /* delname is the name to lookup a delegation for. If NULL rootprime */
1382 /* Lookup the delegation in the cache. If null, then the
1383 * cache needs to be primed for the qclass. */
1385 iq->dp = dns_cache_find_delegation(qstate->env, delname,
1386 delnamelen, iq->qchase.qtype, iq->qchase.qclass,
1387 qstate->region, &iq->deleg_msg,
1388 *qstate->env->now+qstate->prefetch_leeway);
1391 /* If the cache has returned nothing, then we have a
1392 * root priming situation. */
1393 if(iq->dp == NULL) {
1395 /* if under auth zone, no prime needed */
1396 if(!auth_zone_delegpt(qstate, iq, delname, delnamelen))
1397 return error_response(qstate, id,
1398 LDNS_RCODE_SERVFAIL);
1399 if(iq->dp) /* use auth zone dp */
1400 return next_state(iq, INIT_REQUEST_2_STATE);
1401 /* if there is a stub, then no root prime needed */
1402 r = prime_stub(qstate, iq, id, delname,
1405 break; /* got noprime-stub-zone, continue */
1407 return 0; /* stub prime request made */
1408 if(forwards_lookup_root(qstate->env->fwds,
1409 iq->qchase.qclass)) {
1410 /* forward zone root, no root prime needed */
1411 /* fill in some dp - safety belt */
1412 iq->dp = hints_lookup_root(qstate->env->hints,
1415 log_err("internal error: no hints dp");
1416 errinf(qstate, "no hints for this class");
1417 return error_response(qstate, id,
1418 LDNS_RCODE_SERVFAIL);
1420 iq->dp = delegpt_copy(iq->dp, qstate->region);
1422 log_err("out of memory in safety belt");
1423 errinf(qstate, "malloc failure, in safety belt");
1424 return error_response(qstate, id,
1425 LDNS_RCODE_SERVFAIL);
1427 return next_state(iq, INIT_REQUEST_2_STATE);
1429 /* Note that the result of this will set a new
1430 * DelegationPoint based on the result of priming. */
1431 if(!prime_root(qstate, iq, id, iq->qchase.qclass))
1432 return error_response(qstate, id,
1433 LDNS_RCODE_REFUSED);
1435 /* priming creates and sends a subordinate query, with
1436 * this query as the parent. So further processing for
1437 * this event will stop until reactivated by the
1438 * results of priming. */
1441 if(!iq->ratelimit_ok && qstate->prefetch_leeway)
1442 iq->ratelimit_ok = 1; /* allow prefetches, this keeps
1443 otherwise valid data in the cache */
1444 if(!iq->ratelimit_ok && infra_ratelimit_exceeded(
1445 qstate->env->infra_cache, iq->dp->name,
1446 iq->dp->namelen, *qstate->env->now)) {
1447 /* and increment the rate, so that the rate for time
1448 * now will also exceed the rate, keeping cache fresh */
1449 (void)infra_ratelimit_inc(qstate->env->infra_cache,
1450 iq->dp->name, iq->dp->namelen,
1451 *qstate->env->now, &qstate->qinfo,
1453 /* see if we are passed through with slip factor */
1454 if(qstate->env->cfg->ratelimit_factor != 0 &&
1455 ub_random_max(qstate->env->rnd,
1456 qstate->env->cfg->ratelimit_factor) == 1) {
1457 iq->ratelimit_ok = 1;
1458 log_nametypeclass(VERB_ALGO, "ratelimit allowed through for "
1459 "delegation point", iq->dp->name,
1460 LDNS_RR_TYPE_NS, LDNS_RR_CLASS_IN);
1462 lock_basic_lock(&ie->queries_ratelimit_lock);
1463 ie->num_queries_ratelimited++;
1464 lock_basic_unlock(&ie->queries_ratelimit_lock);
1465 log_nametypeclass(VERB_ALGO, "ratelimit exceeded with "
1466 "delegation point", iq->dp->name,
1467 LDNS_RR_TYPE_NS, LDNS_RR_CLASS_IN);
1468 qstate->was_ratelimited = 1;
1469 errinf(qstate, "query was ratelimited");
1470 errinf_dname(qstate, "for zone", iq->dp->name);
1471 return error_response(qstate, id, LDNS_RCODE_SERVFAIL);
1475 /* see if this dp not useless.
1477 * o all NS items are required glue.
1478 * or the query is for NS item that is required glue.
1479 * o no addresses are provided.
1481 * Instead, go up one level, and try to get even further
1482 * If the root was useless, use safety belt information.
1483 * Only check cache returns, because replies for servers
1484 * could be useless but lead to loops (bumping into the
1485 * same server reply) if useless-checked.
1487 if(iter_dp_is_useless(&qstate->qinfo, qstate->query_flags,
1489 struct delegpt* retdp = NULL;
1490 if(!can_have_last_resort(qstate->env, iq->dp->name, iq->dp->namelen, iq->qchase.qclass, &retdp)) {
1492 verbose(VERB_QUERY, "cache has stub "
1493 "or fwd but no addresses, "
1494 "fallback to config");
1495 iq->dp = delegpt_copy(retdp,
1498 log_err("out of memory in "
1499 "stub/fwd fallback");
1500 errinf(qstate, "malloc failure, for fallback to config");
1501 return error_response(qstate,
1502 id, LDNS_RCODE_SERVFAIL);
1506 verbose(VERB_ALGO, "useless dp "
1507 "but cannot go up, servfail");
1508 delegpt_log(VERB_ALGO, iq->dp);
1509 errinf(qstate, "no useful nameservers, "
1510 "and cannot go up");
1511 errinf_dname(qstate, "for zone", iq->dp->name);
1512 return error_response(qstate, id,
1513 LDNS_RCODE_SERVFAIL);
1515 if(dname_is_root(iq->dp->name)) {
1516 /* use safety belt */
1517 verbose(VERB_QUERY, "Cache has root NS but "
1518 "no addresses. Fallback to the safety belt.");
1519 iq->dp = hints_lookup_root(qstate->env->hints,
1521 /* note deleg_msg is from previous lookup,
1522 * but RD is on, so it is not used */
1524 log_err("internal error: no hints dp");
1525 return error_response(qstate, id,
1526 LDNS_RCODE_REFUSED);
1528 iq->dp = delegpt_copy(iq->dp, qstate->region);
1530 log_err("out of memory in safety belt");
1531 errinf(qstate, "malloc failure, in safety belt, for root");
1532 return error_response(qstate, id,
1533 LDNS_RCODE_SERVFAIL);
1538 "cache delegation was useless:");
1539 delegpt_log(VERB_ALGO, iq->dp);
1541 delname = iq->dp->name;
1542 delnamelen = iq->dp->namelen;
1543 dname_remove_label(&delname, &delnamelen);
1548 verbose(VERB_ALGO, "cache delegation returns delegpt");
1549 delegpt_log(VERB_ALGO, iq->dp);
1551 /* Otherwise, set the current delegation point and move on to the
1553 return next_state(iq, INIT_REQUEST_2_STATE);
1557 * Process the second part of the initial request handling. This state
1558 * basically exists so that queries that generate root priming events have
1559 * the same init processing as ones that do not. Request events that reach
1560 * this state must have a valid currentDelegationPoint set.
1562 * This part is primarily handling stub zone priming. Events that reach this
1563 * state must have a current delegation point.
1565 * @param qstate: query state.
1566 * @param iq: iterator query state.
1567 * @param id: module id.
1568 * @return true if the event needs more request processing immediately,
1572 processInitRequest2(struct module_qstate* qstate, struct iter_qstate* iq,
1577 log_query_info(VERB_QUERY, "resolving (init part 2): ",
1580 delname = iq->qchase.qname;
1581 delnamelen = iq->qchase.qname_len;
1582 if(iq->refetch_glue) {
1583 struct iter_hints_stub* stub;
1585 log_err("internal or malloc fail: no dp for refetch");
1586 errinf(qstate, "malloc failure, no delegation info");
1587 return error_response(qstate, id, LDNS_RCODE_SERVFAIL);
1589 /* Do not send queries above stub, do not set delname to dp if
1590 * this is above stub without stub-first. */
1591 stub = hints_lookup_stub(
1592 qstate->env->hints, iq->qchase.qname, iq->qchase.qclass,
1594 if(!stub || !stub->dp->has_parent_side_NS ||
1595 dname_subdomain_c(iq->dp->name, stub->dp->name)) {
1596 delname = iq->dp->name;
1597 delnamelen = iq->dp->namelen;
1600 if(iq->qchase.qtype == LDNS_RR_TYPE_DS || iq->refetch_glue) {
1601 if(!dname_is_root(delname))
1602 dname_remove_label(&delname, &delnamelen);
1603 iq->refetch_glue = 0; /* if CNAME causes restart, no refetch */
1606 /* see if we have an auth zone to answer from, improves dp from cache
1607 * (if any dp from cache) with auth zone dp, if that is lower */
1608 if(!auth_zone_delegpt(qstate, iq, delname, delnamelen))
1609 return error_response(qstate, id, LDNS_RCODE_SERVFAIL);
1611 /* Check to see if we need to prime a stub zone. */
1612 if(prime_stub(qstate, iq, id, delname, iq->qchase.qclass)) {
1613 /* A priming sub request was made */
1617 /* most events just get forwarded to the next state. */
1618 return next_state(iq, INIT_REQUEST_3_STATE);
1622 * Process the third part of the initial request handling. This state exists
1623 * as a separate state so that queries that generate stub priming events
1624 * will get the tail end of the init process but not repeat the stub priming
1627 * @param qstate: query state.
1628 * @param iq: iterator query state.
1629 * @param id: module id.
1630 * @return true, advancing the event to the QUERYTARGETS_STATE.
1633 processInitRequest3(struct module_qstate* qstate, struct iter_qstate* iq,
1636 log_query_info(VERB_QUERY, "resolving (init part 3): ",
1638 /* if the cache reply dp equals a validation anchor or msg has DS,
1639 * then DNSSEC RRSIGs are expected in the reply */
1640 iq->dnssec_expected = iter_indicates_dnssec(qstate->env, iq->dp,
1641 iq->deleg_msg, iq->qchase.qclass);
1643 /* If the RD flag wasn't set, then we just finish with the
1644 * cached referral as the response. */
1645 if(!(qstate->query_flags & BIT_RD) && iq->deleg_msg) {
1646 iq->response = iq->deleg_msg;
1647 if(verbosity >= VERB_ALGO && iq->response)
1648 log_dns_msg("no RD requested, using delegation msg",
1649 &iq->response->qinfo, iq->response->rep);
1650 if(qstate->reply_origin)
1651 sock_list_insert(&qstate->reply_origin, NULL, 0, qstate->region);
1652 return final_state(iq);
1654 /* After this point, unset the RD flag -- this query is going to
1655 * be sent to an auth. server. */
1656 iq->chase_flags &= ~BIT_RD;
1658 /* if dnssec expected, fetch key for the trust-anchor or cached-DS */
1659 if(iq->dnssec_expected && qstate->env->cfg->prefetch_key &&
1660 !(qstate->query_flags&BIT_CD)) {
1661 generate_dnskey_prefetch(qstate, iq, id);
1662 fptr_ok(fptr_whitelist_modenv_detach_subs(
1663 qstate->env->detach_subs));
1664 (*qstate->env->detach_subs)(qstate);
1667 /* Jump to the next state. */
1668 return next_state(iq, QUERYTARGETS_STATE);
1672 * Given a basic query, generate a parent-side "target" query.
1673 * These are subordinate queries for missing delegation point target addresses,
1674 * for which only the parent of the delegation provides correct IP addresses.
1676 * @param qstate: query state.
1677 * @param iq: iterator query state.
1678 * @param id: module id.
1679 * @param name: target qname.
1680 * @param namelen: target qname length.
1681 * @param qtype: target qtype (either A or AAAA).
1682 * @param qclass: target qclass.
1683 * @return true on success, false on failure.
1686 generate_parentside_target_query(struct module_qstate* qstate,
1687 struct iter_qstate* iq, int id, uint8_t* name, size_t namelen,
1688 uint16_t qtype, uint16_t qclass)
1690 struct module_qstate* subq;
1691 if(!generate_sub_request(name, namelen, qtype, qclass, qstate,
1692 id, iq, INIT_REQUEST_STATE, FINISHED_STATE, &subq, 0))
1695 struct iter_qstate* subiq =
1696 (struct iter_qstate*)subq->minfo[id];
1697 /* blacklist the cache - we want to fetch parent stuff */
1698 sock_list_insert(&subq->blacklist, NULL, 0, subq->region);
1699 subiq->query_for_pside_glue = 1;
1700 if(dname_subdomain_c(name, iq->dp->name)) {
1701 subiq->dp = delegpt_copy(iq->dp, subq->region);
1702 subiq->dnssec_expected = iter_indicates_dnssec(
1703 qstate->env, subiq->dp, NULL,
1704 subq->qinfo.qclass);
1705 subiq->refetch_glue = 1;
1707 subiq->dp = dns_cache_find_delegation(qstate->env,
1708 name, namelen, qtype, qclass, subq->region,
1710 *qstate->env->now+subq->prefetch_leeway);
1711 /* if no dp, then it's from root, refetch unneeded */
1713 subiq->dnssec_expected = iter_indicates_dnssec(
1714 qstate->env, subiq->dp, NULL,
1715 subq->qinfo.qclass);
1716 subiq->refetch_glue = 1;
1720 log_nametypeclass(VERB_QUERY, "new pside target", name, qtype, qclass);
1725 * Given a basic query, generate a "target" query. These are subordinate
1726 * queries for missing delegation point target addresses.
1728 * @param qstate: query state.
1729 * @param iq: iterator query state.
1730 * @param id: module id.
1731 * @param name: target qname.
1732 * @param namelen: target qname length.
1733 * @param qtype: target qtype (either A or AAAA).
1734 * @param qclass: target qclass.
1735 * @return true on success, false on failure.
1738 generate_target_query(struct module_qstate* qstate, struct iter_qstate* iq,
1739 int id, uint8_t* name, size_t namelen, uint16_t qtype, uint16_t qclass)
1741 struct module_qstate* subq;
1742 if(!generate_sub_request(name, namelen, qtype, qclass, qstate,
1743 id, iq, INIT_REQUEST_STATE, FINISHED_STATE, &subq, 0))
1745 log_nametypeclass(VERB_QUERY, "new target", name, qtype, qclass);
1750 * Given an event at a certain state, generate zero or more target queries
1751 * for it's current delegation point.
1753 * @param qstate: query state.
1754 * @param iq: iterator query state.
1755 * @param ie: iterator shared global environment.
1756 * @param id: module id.
1757 * @param maxtargets: The maximum number of targets to query for.
1758 * if it is negative, there is no maximum number of targets.
1759 * @param num: returns the number of queries generated and processed,
1760 * which may be zero if there were no missing targets.
1761 * @return false on error.
1764 query_for_targets(struct module_qstate* qstate, struct iter_qstate* iq,
1765 struct iter_env* ie, int id, int maxtargets, int* num)
1767 int query_count = 0;
1768 struct delegpt_ns* ns;
1772 if(iq->depth == ie->max_dependency_depth)
1774 if(iq->depth > 0 && iq->target_count &&
1775 iq->target_count[1] > MAX_TARGET_COUNT) {
1776 char s[LDNS_MAX_DOMAINLEN+1];
1777 dname_str(qstate->qinfo.qname, s);
1778 verbose(VERB_QUERY, "request %s has exceeded the maximum "
1779 "number of glue fetches %d", s, iq->target_count[1]);
1783 iter_mark_cycle_targets(qstate, iq->dp);
1784 missing = (int)delegpt_count_missing_targets(iq->dp);
1785 log_assert(maxtargets != 0); /* that would not be useful */
1787 /* Generate target requests. Basically, any missing targets
1788 * are queried for here, regardless if it is necessary to do
1789 * so to continue processing. */
1790 if(maxtargets < 0 || maxtargets > missing)
1792 else toget = maxtargets;
1797 /* select 'toget' items from the total of 'missing' items */
1798 log_assert(toget <= missing);
1800 /* loop over missing targets */
1801 for(ns = iq->dp->nslist; ns; ns = ns->next) {
1805 /* randomly select this item with probability toget/missing */
1806 if(!iter_ns_probability(qstate->env->rnd, toget, missing)) {
1807 /* do not select this one, next; select toget number
1808 * of items from a list one less in size */
1813 if(ie->supports_ipv6 && !ns->got6) {
1814 /* Send the AAAA request. */
1815 if(!generate_target_query(qstate, iq, id,
1816 ns->name, ns->namelen,
1817 LDNS_RR_TYPE_AAAA, iq->qchase.qclass)) {
1820 qstate->ext_state[id] = module_wait_subquery;
1825 /* Send the A request. */
1826 if(ie->supports_ipv4 && !ns->got4) {
1827 if(!generate_target_query(qstate, iq, id,
1828 ns->name, ns->namelen,
1829 LDNS_RR_TYPE_A, iq->qchase.qclass)) {
1832 qstate->ext_state[id] = module_wait_subquery;
1838 /* mark this target as in progress. */
1847 qstate->ext_state[id] = module_wait_subquery;
1853 * Called by processQueryTargets when it would like extra targets to query
1854 * but it seems to be out of options. At last resort some less appealing
1855 * options are explored. If there are no more options, the result is SERVFAIL
1857 * @param qstate: query state.
1858 * @param iq: iterator query state.
1859 * @param ie: iterator shared global environment.
1860 * @param id: module id.
1861 * @return true if the event requires more request processing immediately,
1865 processLastResort(struct module_qstate* qstate, struct iter_qstate* iq,
1866 struct iter_env* ie, int id)
1868 struct delegpt_ns* ns;
1869 int query_count = 0;
1870 verbose(VERB_ALGO, "No more query targets, attempting last resort");
1873 if(!can_have_last_resort(qstate->env, iq->dp->name, iq->dp->namelen,
1874 iq->qchase.qclass, NULL)) {
1875 /* fail -- no more targets, no more hope of targets, no hope
1877 errinf(qstate, "all the configured stub or forward servers failed,");
1878 errinf_dname(qstate, "at zone", iq->dp->name);
1879 verbose(VERB_QUERY, "configured stub or forward servers failed -- returning SERVFAIL");
1880 return error_response_cache(qstate, id, LDNS_RCODE_SERVFAIL);
1882 if(!iq->dp->has_parent_side_NS && dname_is_root(iq->dp->name)) {
1883 struct delegpt* p = hints_lookup_root(qstate->env->hints,
1886 struct delegpt_addr* a;
1887 iq->chase_flags &= ~BIT_RD; /* go to authorities */
1888 for(ns = p->nslist; ns; ns=ns->next) {
1889 (void)delegpt_add_ns(iq->dp, qstate->region,
1890 ns->name, ns->lame);
1892 for(a = p->target_list; a; a=a->next_target) {
1893 (void)delegpt_add_addr(iq->dp, qstate->region,
1894 &a->addr, a->addrlen, a->bogus,
1895 a->lame, a->tls_auth_name);
1898 iq->dp->has_parent_side_NS = 1;
1899 } else if(!iq->dp->has_parent_side_NS) {
1900 if(!iter_lookup_parent_NS_from_cache(qstate->env, iq->dp,
1901 qstate->region, &qstate->qinfo)
1902 || !iq->dp->has_parent_side_NS) {
1903 /* if: malloc failure in lookup go up to try */
1904 /* if: no parent NS in cache - go up one level */
1905 verbose(VERB_ALGO, "try to grab parent NS");
1906 iq->store_parent_NS = iq->dp;
1907 iq->chase_flags &= ~BIT_RD; /* go to authorities */
1908 iq->deleg_msg = NULL;
1909 iq->refetch_glue = 1;
1910 iq->query_restart_count++;
1912 if(qstate->env->cfg->qname_minimisation)
1913 iq->minimisation_state = INIT_MINIMISE_STATE;
1914 return next_state(iq, INIT_REQUEST_STATE);
1917 /* see if that makes new names available */
1918 if(!cache_fill_missing(qstate->env, iq->qchase.qclass,
1919 qstate->region, iq->dp))
1920 log_err("out of memory in cache_fill_missing");
1921 if(iq->dp->usable_list) {
1922 verbose(VERB_ALGO, "try parent-side-name, w. glue from cache");
1923 return next_state(iq, QUERYTARGETS_STATE);
1925 /* try to fill out parent glue from cache */
1926 if(iter_lookup_parent_glue_from_cache(qstate->env, iq->dp,
1927 qstate->region, &qstate->qinfo)) {
1928 /* got parent stuff from cache, see if we can continue */
1929 verbose(VERB_ALGO, "try parent-side glue from cache");
1930 return next_state(iq, QUERYTARGETS_STATE);
1932 /* query for an extra name added by the parent-NS record */
1933 if(delegpt_count_missing_targets(iq->dp) > 0) {
1935 verbose(VERB_ALGO, "try parent-side target name");
1936 if(!query_for_targets(qstate, iq, ie, id, 1, &qs)) {
1937 errinf(qstate, "could not fetch nameserver");
1938 errinf_dname(qstate, "at zone", iq->dp->name);
1939 return error_response(qstate, id, LDNS_RCODE_SERVFAIL);
1941 iq->num_target_queries += qs;
1942 target_count_increase(iq, qs);
1944 qstate->ext_state[id] = module_wait_subquery;
1945 return 0; /* and wait for them */
1948 if(iq->depth == ie->max_dependency_depth) {
1949 verbose(VERB_QUERY, "maxdepth and need more nameservers, fail");
1950 errinf(qstate, "cannot fetch more nameservers because at max dependency depth");
1951 return error_response_cache(qstate, id, LDNS_RCODE_SERVFAIL);
1953 if(iq->depth > 0 && iq->target_count &&
1954 iq->target_count[1] > MAX_TARGET_COUNT) {
1955 char s[LDNS_MAX_DOMAINLEN+1];
1956 dname_str(qstate->qinfo.qname, s);
1957 verbose(VERB_QUERY, "request %s has exceeded the maximum "
1958 "number of glue fetches %d", s, iq->target_count[1]);
1959 errinf(qstate, "exceeded the maximum number of glue fetches");
1960 return error_response_cache(qstate, id, LDNS_RCODE_SERVFAIL);
1962 /* mark cycle targets for parent-side lookups */
1963 iter_mark_pside_cycle_targets(qstate, iq->dp);
1964 /* see if we can issue queries to get nameserver addresses */
1965 /* this lookup is not randomized, but sequential. */
1966 for(ns = iq->dp->nslist; ns; ns = ns->next) {
1967 /* if this nameserver is at a delegation point, but that
1968 * delegation point is a stub and we cannot go higher, skip*/
1969 if( ((ie->supports_ipv6 && !ns->done_pside6) ||
1970 (ie->supports_ipv4 && !ns->done_pside4)) &&
1971 !can_have_last_resort(qstate->env, ns->name, ns->namelen,
1972 iq->qchase.qclass, NULL)) {
1973 log_nametypeclass(VERB_ALGO, "cannot pside lookup ns "
1974 "because it is also a stub/forward,",
1975 ns->name, LDNS_RR_TYPE_NS, iq->qchase.qclass);
1976 if(ie->supports_ipv6) ns->done_pside6 = 1;
1977 if(ie->supports_ipv4) ns->done_pside4 = 1;
1980 /* query for parent-side A and AAAA for nameservers */
1981 if(ie->supports_ipv6 && !ns->done_pside6) {
1982 /* Send the AAAA request. */
1983 if(!generate_parentside_target_query(qstate, iq, id,
1984 ns->name, ns->namelen,
1985 LDNS_RR_TYPE_AAAA, iq->qchase.qclass)) {
1986 errinf_dname(qstate, "could not generate nameserver AAAA lookup for", ns->name);
1987 return error_response(qstate, id,
1988 LDNS_RCODE_SERVFAIL);
1990 ns->done_pside6 = 1;
1993 if(ie->supports_ipv4 && !ns->done_pside4) {
1994 /* Send the A request. */
1995 if(!generate_parentside_target_query(qstate, iq, id,
1996 ns->name, ns->namelen,
1997 LDNS_RR_TYPE_A, iq->qchase.qclass)) {
1998 errinf_dname(qstate, "could not generate nameserver A lookup for", ns->name);
1999 return error_response(qstate, id,
2000 LDNS_RCODE_SERVFAIL);
2002 ns->done_pside4 = 1;
2005 if(query_count != 0) { /* suspend to await results */
2006 verbose(VERB_ALGO, "try parent-side glue lookup");
2007 iq->num_target_queries += query_count;
2008 target_count_increase(iq, query_count);
2009 qstate->ext_state[id] = module_wait_subquery;
2014 /* if this was a parent-side glue query itself, then store that
2015 * failure in cache. */
2016 if(!qstate->no_cache_store && iq->query_for_pside_glue
2018 iter_store_parentside_neg(qstate->env, &qstate->qinfo,
2019 iq->deleg_msg?iq->deleg_msg->rep:
2020 (iq->response?iq->response->rep:NULL));
2022 errinf(qstate, "all servers for this domain failed,");
2023 errinf_dname(qstate, "at zone", iq->dp->name);
2024 verbose(VERB_QUERY, "out of query targets -- returning SERVFAIL");
2025 /* fail -- no more targets, no more hope of targets, no hope
2027 return error_response_cache(qstate, id, LDNS_RCODE_SERVFAIL);
2031 * Try to find the NS record set that will resolve a qtype DS query. Due
2032 * to grandparent/grandchild reasons we did not get a proper lookup right
2033 * away. We need to create type NS queries until we get the right parent
2034 * for this lookup. We remove labels from the query to find the right point.
2035 * If we end up at the old dp name, then there is no solution.
2037 * @param qstate: query state.
2038 * @param iq: iterator query state.
2039 * @param id: module id.
2040 * @return true if the event requires more immediate processing, false if
2041 * not. This is generally only true when forwarding the request to
2042 * the final state (i.e., on answer).
2045 processDSNSFind(struct module_qstate* qstate, struct iter_qstate* iq, int id)
2047 struct module_qstate* subq = NULL;
2048 verbose(VERB_ALGO, "processDSNSFind");
2050 if(!iq->dsns_point) {
2052 iq->dsns_point = iq->qchase.qname;
2053 iq->dsns_point_len = iq->qchase.qname_len;
2055 /* robustcheck for internal error: we are not underneath the dp */
2056 if(!dname_subdomain_c(iq->dsns_point, iq->dp->name)) {
2057 errinf_dname(qstate, "for DS query parent-child nameserver search the query is not under the zone", iq->dp->name);
2058 return error_response_cache(qstate, id, LDNS_RCODE_SERVFAIL);
2061 /* go up one (more) step, until we hit the dp, if so, end */
2062 dname_remove_label(&iq->dsns_point, &iq->dsns_point_len);
2063 if(query_dname_compare(iq->dsns_point, iq->dp->name) == 0) {
2064 /* there was no inbetween nameserver, use the old delegation
2065 * point again. And this time, because dsns_point is nonNULL
2066 * we are going to accept the (bad) result */
2067 iq->state = QUERYTARGETS_STATE;
2070 iq->state = DSNS_FIND_STATE;
2072 /* spawn NS lookup (validation not needed, this is for DS lookup) */
2073 log_nametypeclass(VERB_ALGO, "fetch nameservers",
2074 iq->dsns_point, LDNS_RR_TYPE_NS, iq->qchase.qclass);
2075 if(!generate_sub_request(iq->dsns_point, iq->dsns_point_len,
2076 LDNS_RR_TYPE_NS, iq->qchase.qclass, qstate, id, iq,
2077 INIT_REQUEST_STATE, FINISHED_STATE, &subq, 0)) {
2078 errinf_dname(qstate, "for DS query parent-child nameserver search, could not generate NS lookup for", iq->dsns_point);
2079 return error_response_cache(qstate, id, LDNS_RCODE_SERVFAIL);
2086 * This is the request event state where the request will be sent to one of
2087 * its current query targets. This state also handles issuing target lookup
2088 * queries for missing target IP addresses. Queries typically iterate on
2089 * this state, both when they are just trying different targets for a given
2090 * delegation point, and when they change delegation points. This state
2091 * roughly corresponds to RFC 1034 algorithm steps 3 and 4.
2093 * @param qstate: query state.
2094 * @param iq: iterator query state.
2095 * @param ie: iterator shared global environment.
2096 * @param id: module id.
2097 * @return true if the event requires more request processing immediately,
2098 * false if not. This state only returns true when it is generating
2099 * a SERVFAIL response because the query has hit a dead end.
2102 processQueryTargets(struct module_qstate* qstate, struct iter_qstate* iq,
2103 struct iter_env* ie, int id)
2106 struct delegpt_addr* target;
2107 struct outbound_entry* outq;
2108 int auth_fallback = 0;
2109 uint8_t* qout_orig = NULL;
2110 size_t qout_orig_len = 0;
2112 /* NOTE: a request will encounter this state for each target it
2113 * needs to send a query to. That is, at least one per referral,
2114 * more if some targets timeout or return throwaway answers. */
2116 log_query_info(VERB_QUERY, "processQueryTargets:", &qstate->qinfo);
2117 verbose(VERB_ALGO, "processQueryTargets: targetqueries %d, "
2118 "currentqueries %d sentcount %d", iq->num_target_queries,
2119 iq->num_current_queries, iq->sent_count);
2121 /* Make sure that we haven't run away */
2122 /* FIXME: is this check even necessary? */
2123 if(iq->referral_count > MAX_REFERRAL_COUNT) {
2124 verbose(VERB_QUERY, "request has exceeded the maximum "
2125 "number of referrrals with %d", iq->referral_count);
2126 errinf(qstate, "exceeded the maximum of referrals");
2127 return error_response(qstate, id, LDNS_RCODE_SERVFAIL);
2129 if(iq->sent_count > MAX_SENT_COUNT) {
2130 verbose(VERB_QUERY, "request has exceeded the maximum "
2131 "number of sends with %d", iq->sent_count);
2132 errinf(qstate, "exceeded the maximum number of sends");
2133 return error_response(qstate, id, LDNS_RCODE_SERVFAIL);
2136 /* Make sure we have a delegation point, otherwise priming failed
2137 * or another failure occurred */
2139 verbose(VERB_QUERY, "Failed to get a delegation, giving up");
2140 errinf(qstate, "failed to get a delegation (eg. prime failure)");
2141 return error_response(qstate, id, LDNS_RCODE_SERVFAIL);
2143 if(!ie->supports_ipv6)
2144 delegpt_no_ipv6(iq->dp);
2145 if(!ie->supports_ipv4)
2146 delegpt_no_ipv4(iq->dp);
2147 delegpt_log(VERB_ALGO, iq->dp);
2149 if(iq->num_current_queries>0) {
2150 /* already busy answering a query, this restart is because
2151 * more delegpt addrs became available, wait for existing
2153 verbose(VERB_ALGO, "woke up, but wait for outstanding query");
2154 qstate->ext_state[id] = module_wait_reply;
2158 if(iq->minimisation_state == INIT_MINIMISE_STATE
2159 && !(iq->chase_flags & BIT_RD)) {
2160 /* (Re)set qinfo_out to (new) delegation point, except when
2161 * qinfo_out is already a subdomain of dp. This happens when
2162 * increasing by more than one label at once (QNAMEs with more
2163 * than MAX_MINIMISE_COUNT labels). */
2164 if(!(iq->qinfo_out.qname_len
2165 && dname_subdomain_c(iq->qchase.qname,
2166 iq->qinfo_out.qname)
2167 && dname_subdomain_c(iq->qinfo_out.qname,
2169 iq->qinfo_out.qname = iq->dp->name;
2170 iq->qinfo_out.qname_len = iq->dp->namelen;
2171 iq->qinfo_out.qtype = LDNS_RR_TYPE_A;
2172 iq->qinfo_out.qclass = iq->qchase.qclass;
2173 iq->qinfo_out.local_alias = NULL;
2174 iq->minimise_count = 0;
2177 iq->minimisation_state = MINIMISE_STATE;
2179 if(iq->minimisation_state == MINIMISE_STATE) {
2180 int qchaselabs = dname_count_labels(iq->qchase.qname);
2181 int labdiff = qchaselabs -
2182 dname_count_labels(iq->qinfo_out.qname);
2184 qout_orig = iq->qinfo_out.qname;
2185 qout_orig_len = iq->qinfo_out.qname_len;
2186 iq->qinfo_out.qname = iq->qchase.qname;
2187 iq->qinfo_out.qname_len = iq->qchase.qname_len;
2188 iq->minimise_count++;
2189 iq->minimise_timeout_count = 0;
2191 iter_dec_attempts(iq->dp, 1);
2193 /* Limit number of iterations for QNAMEs with more
2194 * than MAX_MINIMISE_COUNT labels. Send first MINIMISE_ONE_LAB
2195 * labels of QNAME always individually.
2197 if(qchaselabs > MAX_MINIMISE_COUNT && labdiff > 1 &&
2198 iq->minimise_count > MINIMISE_ONE_LAB) {
2199 if(iq->minimise_count < MAX_MINIMISE_COUNT) {
2200 int multilabs = qchaselabs - 1 -
2202 int extralabs = multilabs /
2203 MINIMISE_MULTIPLE_LABS;
2205 if (MAX_MINIMISE_COUNT - iq->minimise_count >=
2206 multilabs % MINIMISE_MULTIPLE_LABS)
2207 /* Default behaviour is to add 1 label
2208 * every iteration. Therefore, decrement
2209 * the extralabs by 1 */
2211 if (extralabs < labdiff)
2212 labdiff -= extralabs;
2216 /* Last minimised iteration, send all labels with
2223 verbose(VERB_QUERY, "removing %d labels", labdiff-1);
2224 dname_remove_labels(&iq->qinfo_out.qname,
2225 &iq->qinfo_out.qname_len,
2228 if(labdiff < 1 || (labdiff < 2
2229 && (iq->qchase.qtype == LDNS_RR_TYPE_DS
2230 || iq->qchase.qtype == LDNS_RR_TYPE_A)))
2231 /* Stop minimising this query, resolve "as usual" */
2232 iq->minimisation_state = DONOT_MINIMISE_STATE;
2233 else if(!qstate->no_cache_lookup) {
2234 struct dns_msg* msg = dns_cache_lookup(qstate->env,
2235 iq->qinfo_out.qname, iq->qinfo_out.qname_len,
2236 iq->qinfo_out.qtype, iq->qinfo_out.qclass,
2237 qstate->query_flags, qstate->region,
2238 qstate->env->scratch, 0);
2239 if(msg && msg->rep->an_numrrsets == 0
2240 && FLAGS_GET_RCODE(msg->rep->flags) ==
2242 /* no need to send query if it is already
2243 * cached as NOERROR/NODATA */
2247 if(iq->minimisation_state == SKIP_MINIMISE_STATE) {
2248 if(iq->minimise_timeout_count < MAX_MINIMISE_TIMEOUT_COUNT)
2249 /* Do not increment qname, continue incrementing next
2251 iq->minimisation_state = MINIMISE_STATE;
2252 else if(!qstate->env->cfg->qname_minimisation_strict)
2253 /* Too many time-outs detected for this QNAME and QTYPE.
2254 * We give up, disable QNAME minimisation. */
2255 iq->minimisation_state = DONOT_MINIMISE_STATE;
2257 if(iq->minimisation_state == DONOT_MINIMISE_STATE)
2258 iq->qinfo_out = iq->qchase;
2260 /* now find an answer to this query */
2261 /* see if authority zones have an answer */
2262 /* now we know the dp, we can check the auth zone for locally hosted
2264 if(!iq->auth_zone_avoid && qstate->blacklist) {
2265 if(auth_zones_can_fallback(qstate->env->auth_zones,
2266 iq->dp->name, iq->dp->namelen, iq->qinfo_out.qclass)) {
2267 /* if cache is blacklisted and this zone allows us
2268 * to fallback to the internet, then do so, and
2269 * fetch results from the internet servers */
2270 iq->auth_zone_avoid = 1;
2273 if(iq->auth_zone_avoid) {
2274 iq->auth_zone_avoid = 0;
2276 } else if(auth_zones_lookup(qstate->env->auth_zones, &iq->qinfo_out,
2277 qstate->region, &iq->response, &auth_fallback, iq->dp->name,
2279 /* use this as a response to be processed by the iterator */
2280 if(verbosity >= VERB_ALGO) {
2281 log_dns_msg("msg from auth zone",
2282 &iq->response->qinfo, iq->response->rep);
2284 if((iq->chase_flags&BIT_RD) && !(iq->response->rep->flags&BIT_AA)) {
2285 verbose(VERB_ALGO, "forwarder, ignoring referral from auth zone");
2287 lock_rw_wrlock(&qstate->env->auth_zones->lock);
2288 qstate->env->auth_zones->num_query_up++;
2289 lock_rw_unlock(&qstate->env->auth_zones->lock);
2290 iq->num_current_queries++;
2291 iq->chase_to_rd = 0;
2292 iq->dnssec_lame_query = 0;
2293 iq->auth_zone_response = 1;
2294 return next_state(iq, QUERY_RESP_STATE);
2297 iq->auth_zone_response = 0;
2298 if(auth_fallback == 0) {
2299 /* like we got servfail from the auth zone lookup, and
2300 * no internet fallback */
2301 verbose(VERB_ALGO, "auth zone lookup failed, no fallback,"
2303 errinf(qstate, "auth zone lookup failed, fallback is off");
2304 return error_response(qstate, id, LDNS_RCODE_SERVFAIL);
2306 if(iq->dp->auth_dp) {
2307 /* we wanted to fallback, but had no delegpt, only the
2308 * auth zone generated delegpt, create an actual one */
2309 iq->auth_zone_avoid = 1;
2310 return next_state(iq, INIT_REQUEST_STATE);
2312 /* but mostly, fallback==1 (like, when no such auth zone exists)
2313 * and we continue with lookups */
2316 /* < not <=, because although the array is large enough for <=, the
2317 * generated query will immediately be discarded due to depth and
2318 * that servfail is cached, which is not good as opportunism goes. */
2319 if(iq->depth < ie->max_dependency_depth
2320 && iq->sent_count < TARGET_FETCH_STOP) {
2321 tf_policy = ie->target_fetch_policy[iq->depth];
2324 /* if in 0x20 fallback get as many targets as possible */
2325 if(iq->caps_fallback) {
2327 size_t naddr, nres, navail;
2328 if(!query_for_targets(qstate, iq, ie, id, -1, &extra)) {
2329 errinf(qstate, "could not fetch nameservers for 0x20 fallback");
2330 return error_response(qstate, id, LDNS_RCODE_SERVFAIL);
2332 iq->num_target_queries += extra;
2333 target_count_increase(iq, extra);
2334 if(iq->num_target_queries > 0) {
2335 /* wait to get all targets, we want to try em */
2336 verbose(VERB_ALGO, "wait for all targets for fallback");
2337 qstate->ext_state[id] = module_wait_reply;
2338 /* undo qname minimise step because we'll get back here
2340 if(qout_orig && iq->minimise_count > 0) {
2341 iq->minimise_count--;
2342 iq->qinfo_out.qname = qout_orig;
2343 iq->qinfo_out.qname_len = qout_orig_len;
2347 /* did we do enough fallback queries already? */
2348 delegpt_count_addr(iq->dp, &naddr, &nres, &navail);
2349 /* the current caps_server is the number of fallbacks sent.
2350 * the original query is one that matched too, so we have
2351 * caps_server+1 number of matching queries now */
2352 if(iq->caps_server+1 >= naddr*3 ||
2353 iq->caps_server*2+2 >= MAX_SENT_COUNT) {
2354 /* *2 on sentcount check because ipv6 may fail */
2355 /* we're done, process the response */
2356 verbose(VERB_ALGO, "0x20 fallback had %d responses "
2357 "match for %d wanted, done.",
2358 (int)iq->caps_server+1, (int)naddr*3);
2359 iq->response = iq->caps_response;
2360 iq->caps_fallback = 0;
2361 iter_dec_attempts(iq->dp, 3); /* space for fallback */
2362 iq->num_current_queries++; /* RespState decrements it*/
2363 iq->referral_count++; /* make sure we don't loop */
2365 iq->state = QUERY_RESP_STATE;
2368 verbose(VERB_ALGO, "0x20 fallback number %d",
2369 (int)iq->caps_server);
2371 /* if there is a policy to fetch missing targets
2372 * opportunistically, do it. we rely on the fact that once a
2373 * query (or queries) for a missing name have been issued,
2374 * they will not show up again. */
2375 } else if(tf_policy != 0) {
2377 verbose(VERB_ALGO, "attempt to get extra %d targets",
2379 (void)query_for_targets(qstate, iq, ie, id, tf_policy, &extra);
2380 /* errors ignored, these targets are not strictly necessary for
2381 * this result, we do not have to reply with SERVFAIL */
2382 iq->num_target_queries += extra;
2383 target_count_increase(iq, extra);
2386 /* Add the current set of unused targets to our queue. */
2387 delegpt_add_unused_targets(iq->dp);
2389 /* Select the next usable target, filtering out unsuitable targets. */
2390 target = iter_server_selection(ie, qstate->env, iq->dp,
2391 iq->dp->name, iq->dp->namelen, iq->qchase.qtype,
2392 &iq->dnssec_lame_query, &iq->chase_to_rd,
2393 iq->num_target_queries, qstate->blacklist,
2394 qstate->prefetch_leeway);
2396 /* If no usable target was selected... */
2398 /* Here we distinguish between three states: generate a new
2399 * target query, just wait, or quit (with a SERVFAIL).
2400 * We have the following information: number of active
2401 * target queries, number of active current queries,
2402 * the presence of missing targets at this delegation
2403 * point, and the given query target policy. */
2405 /* Check for the wait condition. If this is true, then
2406 * an action must be taken. */
2407 if(iq->num_target_queries==0 && iq->num_current_queries==0) {
2408 /* If there is nothing to wait for, then we need
2409 * to distinguish between generating (a) new target
2410 * query, or failing. */
2411 if(delegpt_count_missing_targets(iq->dp) > 0) {
2413 verbose(VERB_ALGO, "querying for next "
2415 if(!query_for_targets(qstate, iq, ie, id,
2417 errinf(qstate, "could not fetch nameserver");
2418 errinf_dname(qstate, "at zone", iq->dp->name);
2419 return error_response(qstate, id,
2420 LDNS_RCODE_SERVFAIL);
2423 delegpt_count_missing_targets(iq->dp) == 0){
2424 /* it looked like there were missing
2425 * targets, but they did not turn up.
2426 * Try the bad choices again (if any),
2427 * when we get back here missing==0,
2428 * so this is not a loop. */
2431 iq->num_target_queries += qs;
2432 target_count_increase(iq, qs);
2434 /* Since a target query might have been made, we
2435 * need to check again. */
2436 if(iq->num_target_queries == 0) {
2437 /* if in capsforid fallback, instead of last
2438 * resort, we agree with the current reply
2439 * we have (if any) (our count of addrs bad)*/
2440 if(iq->caps_fallback && iq->caps_reply) {
2441 /* we're done, process the response */
2442 verbose(VERB_ALGO, "0x20 fallback had %d responses, "
2443 "but no more servers except "
2444 "last resort, done.",
2445 (int)iq->caps_server+1);
2446 iq->response = iq->caps_response;
2447 iq->caps_fallback = 0;
2448 iter_dec_attempts(iq->dp, 3); /* space for fallback */
2449 iq->num_current_queries++; /* RespState decrements it*/
2450 iq->referral_count++; /* make sure we don't loop */
2452 iq->state = QUERY_RESP_STATE;
2455 return processLastResort(qstate, iq, ie, id);
2459 /* otherwise, we have no current targets, so submerge
2460 * until one of the target or direct queries return. */
2461 if(iq->num_target_queries>0 && iq->num_current_queries>0) {
2462 verbose(VERB_ALGO, "no current targets -- waiting "
2463 "for %d targets to resolve or %d outstanding"
2464 " queries to respond", iq->num_target_queries,
2465 iq->num_current_queries);
2466 qstate->ext_state[id] = module_wait_reply;
2467 } else if(iq->num_target_queries>0) {
2468 verbose(VERB_ALGO, "no current targets -- waiting "
2469 "for %d targets to resolve.",
2470 iq->num_target_queries);
2471 qstate->ext_state[id] = module_wait_subquery;
2473 verbose(VERB_ALGO, "no current targets -- waiting "
2474 "for %d outstanding queries to respond.",
2475 iq->num_current_queries);
2476 qstate->ext_state[id] = module_wait_reply;
2478 /* undo qname minimise step because we'll get back here
2480 if(qout_orig && iq->minimise_count > 0) {
2481 iq->minimise_count--;
2482 iq->qinfo_out.qname = qout_orig;
2483 iq->qinfo_out.qname_len = qout_orig_len;
2488 /* if not forwarding, check ratelimits per delegationpoint name */
2489 if(!(iq->chase_flags & BIT_RD) && !iq->ratelimit_ok) {
2490 if(!infra_ratelimit_inc(qstate->env->infra_cache, iq->dp->name,
2491 iq->dp->namelen, *qstate->env->now, &qstate->qinfo,
2493 lock_basic_lock(&ie->queries_ratelimit_lock);
2494 ie->num_queries_ratelimited++;
2495 lock_basic_unlock(&ie->queries_ratelimit_lock);
2496 verbose(VERB_ALGO, "query exceeded ratelimits");
2497 qstate->was_ratelimited = 1;
2498 errinf_dname(qstate, "exceeded ratelimit for zone",
2500 return error_response(qstate, id, LDNS_RCODE_SERVFAIL);
2504 /* We have a valid target. */
2505 if(verbosity >= VERB_QUERY) {
2506 log_query_info(VERB_QUERY, "sending query:", &iq->qinfo_out);
2507 log_name_addr(VERB_QUERY, "sending to target:", iq->dp->name,
2508 &target->addr, target->addrlen);
2509 verbose(VERB_ALGO, "dnssec status: %s%s",
2510 iq->dnssec_expected?"expected": "not expected",
2511 iq->dnssec_lame_query?" but lame_query anyway": "");
2513 fptr_ok(fptr_whitelist_modenv_send_query(qstate->env->send_query));
2514 outq = (*qstate->env->send_query)(&iq->qinfo_out,
2515 iq->chase_flags | (iq->chase_to_rd?BIT_RD:0),
2516 /* unset CD if to forwarder(RD set) and not dnssec retry
2517 * (blacklist nonempty) and no trust-anchors are configured
2518 * above the qname or on the first attempt when dnssec is on */
2519 EDNS_DO| ((iq->chase_to_rd||(iq->chase_flags&BIT_RD)!=0)&&
2520 !qstate->blacklist&&(!iter_qname_indicates_dnssec(qstate->env,
2521 &iq->qinfo_out)||target->attempts==1)?0:BIT_CD),
2522 iq->dnssec_expected, iq->caps_fallback || is_caps_whitelisted(
2523 ie, iq), &target->addr, target->addrlen,
2524 iq->dp->name, iq->dp->namelen,
2525 (iq->dp->ssl_upstream || qstate->env->cfg->ssl_upstream),
2526 target->tls_auth_name, qstate);
2528 log_addr(VERB_DETAIL, "error sending query to auth server",
2529 &target->addr, target->addrlen);
2530 if(!(iq->chase_flags & BIT_RD) && !iq->ratelimit_ok)
2531 infra_ratelimit_dec(qstate->env->infra_cache, iq->dp->name,
2532 iq->dp->namelen, *qstate->env->now);
2533 if(qstate->env->cfg->qname_minimisation)
2534 iq->minimisation_state = SKIP_MINIMISE_STATE;
2535 return next_state(iq, QUERYTARGETS_STATE);
2537 outbound_list_insert(&iq->outlist, outq);
2538 iq->num_current_queries++;
2540 qstate->ext_state[id] = module_wait_reply;
2545 /** find NS rrset in given list */
2546 static struct ub_packed_rrset_key*
2547 find_NS(struct reply_info* rep, size_t from, size_t to)
2550 for(i=from; i<to; i++) {
2551 if(ntohs(rep->rrsets[i]->rk.type) == LDNS_RR_TYPE_NS)
2552 return rep->rrsets[i];
2559 * Process the query response. All queries end up at this state first. This
2560 * process generally consists of analyzing the response and routing the
2561 * event to the next state (either bouncing it back to a request state, or
2562 * terminating the processing for this event).
2564 * @param qstate: query state.
2565 * @param iq: iterator query state.
2566 * @param id: module id.
2567 * @return true if the event requires more immediate processing, false if
2568 * not. This is generally only true when forwarding the request to
2569 * the final state (i.e., on answer).
2572 processQueryResponse(struct module_qstate* qstate, struct iter_qstate* iq,
2576 enum response_type type;
2577 iq->num_current_queries--;
2579 if(!inplace_cb_query_response_call(qstate->env, qstate, iq->response))
2580 log_err("unable to call query_response callback");
2582 if(iq->response == NULL) {
2583 /* Don't increment qname when QNAME minimisation is enabled */
2584 if(qstate->env->cfg->qname_minimisation) {
2585 iq->minimise_timeout_count++;
2586 iq->minimisation_state = SKIP_MINIMISE_STATE;
2588 iq->chase_to_rd = 0;
2589 iq->dnssec_lame_query = 0;
2590 verbose(VERB_ALGO, "query response was timeout");
2591 return next_state(iq, QUERYTARGETS_STATE);
2593 type = response_type_from_server(
2594 (int)((iq->chase_flags&BIT_RD) || iq->chase_to_rd),
2595 iq->response, &iq->qinfo_out, iq->dp);
2596 iq->chase_to_rd = 0;
2597 if(type == RESPONSE_TYPE_REFERRAL && (iq->chase_flags&BIT_RD) &&
2598 !iq->auth_zone_response) {
2599 /* When forwarding (RD bit is set), we handle referrals
2600 * differently. No queries should be sent elsewhere */
2601 type = RESPONSE_TYPE_ANSWER;
2603 if(!qstate->env->cfg->disable_dnssec_lame_check && iq->dnssec_expected
2604 && !iq->dnssec_lame_query &&
2605 !(iq->chase_flags&BIT_RD)
2606 && iq->sent_count < DNSSEC_LAME_DETECT_COUNT
2607 && type != RESPONSE_TYPE_LAME
2608 && type != RESPONSE_TYPE_REC_LAME
2609 && type != RESPONSE_TYPE_THROWAWAY
2610 && type != RESPONSE_TYPE_UNTYPED) {
2611 /* a possible answer, see if it is missing DNSSEC */
2612 /* but not when forwarding, so we dont mark fwder lame */
2613 if(!iter_msg_has_dnssec(iq->response)) {
2614 /* Mark this address as dnsseclame in this dp,
2615 * because that will make serverselection disprefer
2616 * it, but also, once it is the only final option,
2617 * use dnssec-lame-bypass if it needs to query there.*/
2619 struct delegpt_addr* a = delegpt_find_addr(
2620 iq->dp, &qstate->reply->addr,
2621 qstate->reply->addrlen);
2622 if(a) a->dnsseclame = 1;
2624 /* test the answer is from the zone we expected,
2625 * otherwise, (due to parent,child on same server), we
2626 * might mark the server,zone lame inappropriately */
2627 if(!iter_msg_from_zone(iq->response, iq->dp, type,
2629 qstate->reply = NULL;
2630 type = RESPONSE_TYPE_LAME;
2633 } else iq->dnssec_lame_query = 0;
2634 /* see if referral brings us close to the target */
2635 if(type == RESPONSE_TYPE_REFERRAL) {
2636 struct ub_packed_rrset_key* ns = find_NS(
2637 iq->response->rep, iq->response->rep->an_numrrsets,
2638 iq->response->rep->an_numrrsets
2639 + iq->response->rep->ns_numrrsets);
2640 if(!ns) ns = find_NS(iq->response->rep, 0,
2641 iq->response->rep->an_numrrsets);
2642 if(!ns || !dname_strict_subdomain_c(ns->rk.dname, iq->dp->name)
2643 || !dname_subdomain_c(iq->qchase.qname, ns->rk.dname)){
2644 verbose(VERB_ALGO, "bad referral, throwaway");
2645 type = RESPONSE_TYPE_THROWAWAY;
2647 iter_scrub_ds(iq->response, ns, iq->dp->name);
2648 } else iter_scrub_ds(iq->response, NULL, NULL);
2649 if(type == RESPONSE_TYPE_THROWAWAY &&
2650 FLAGS_GET_RCODE(iq->response->rep->flags) == LDNS_RCODE_YXDOMAIN) {
2651 /* YXDOMAIN is a permanent error, no need to retry */
2652 type = RESPONSE_TYPE_ANSWER;
2654 if(type == RESPONSE_TYPE_CNAME && iq->response->rep->an_numrrsets >= 1
2655 && ntohs(iq->response->rep->rrsets[0]->rk.type) == LDNS_RR_TYPE_DNAME) {
2656 uint8_t* sname = NULL;
2657 size_t snamelen = 0;
2658 get_cname_target(iq->response->rep->rrsets[0], &sname,
2660 if(snamelen && dname_subdomain_c(sname, iq->response->rep->rrsets[0]->rk.dname)) {
2661 /* DNAME to a subdomain loop; do not recurse */
2662 type = RESPONSE_TYPE_ANSWER;
2664 } else if(type == RESPONSE_TYPE_CNAME &&
2665 iq->qchase.qtype == LDNS_RR_TYPE_CNAME &&
2666 iq->minimisation_state == MINIMISE_STATE &&
2667 query_dname_compare(iq->qchase.qname, iq->qinfo_out.qname) == 0) {
2668 /* The minimised query for full QTYPE and hidden QTYPE can be
2669 * classified as CNAME response type, even when the original
2670 * QTYPE=CNAME. This should be treated as answer response type.
2672 type = RESPONSE_TYPE_ANSWER;
2675 /* handle each of the type cases */
2676 if(type == RESPONSE_TYPE_ANSWER) {
2677 /* ANSWER type responses terminate the query algorithm,
2678 * so they sent on their */
2679 if(verbosity >= VERB_DETAIL) {
2680 verbose(VERB_DETAIL, "query response was %s",
2681 FLAGS_GET_RCODE(iq->response->rep->flags)
2682 ==LDNS_RCODE_NXDOMAIN?"NXDOMAIN ANSWER":
2683 (iq->response->rep->an_numrrsets?"ANSWER":
2686 /* if qtype is DS, check we have the right level of answer,
2687 * like grandchild answer but we need the middle, reject it */
2688 if(iq->qchase.qtype == LDNS_RR_TYPE_DS && !iq->dsns_point
2689 && !(iq->chase_flags&BIT_RD)
2690 && iter_ds_toolow(iq->response, iq->dp)
2691 && iter_dp_cangodown(&iq->qchase, iq->dp)) {
2692 /* close down outstanding requests to be discarded */
2693 outbound_list_clear(&iq->outlist);
2694 iq->num_current_queries = 0;
2695 fptr_ok(fptr_whitelist_modenv_detach_subs(
2696 qstate->env->detach_subs));
2697 (*qstate->env->detach_subs)(qstate);
2698 iq->num_target_queries = 0;
2699 return processDSNSFind(qstate, iq, id);
2701 if(!qstate->no_cache_store)
2702 iter_dns_store(qstate->env, &iq->response->qinfo,
2703 iq->response->rep, 0, qstate->prefetch_leeway,
2704 iq->dp&&iq->dp->has_parent_side_NS,
2705 qstate->region, qstate->query_flags);
2706 /* close down outstanding requests to be discarded */
2707 outbound_list_clear(&iq->outlist);
2708 iq->num_current_queries = 0;
2709 fptr_ok(fptr_whitelist_modenv_detach_subs(
2710 qstate->env->detach_subs));
2711 (*qstate->env->detach_subs)(qstate);
2712 iq->num_target_queries = 0;
2714 sock_list_insert(&qstate->reply_origin,
2715 &qstate->reply->addr, qstate->reply->addrlen,
2717 if(iq->minimisation_state != DONOT_MINIMISE_STATE
2718 && !(iq->chase_flags & BIT_RD)) {
2719 if(FLAGS_GET_RCODE(iq->response->rep->flags) !=
2720 LDNS_RCODE_NOERROR) {
2721 if(qstate->env->cfg->qname_minimisation_strict) {
2722 if(FLAGS_GET_RCODE(iq->response->rep->flags) ==
2723 LDNS_RCODE_NXDOMAIN) {
2724 iter_scrub_nxdomain(iq->response);
2725 return final_state(iq);
2727 return error_response(qstate, id,
2728 LDNS_RCODE_SERVFAIL);
2730 /* Best effort qname-minimisation.
2731 * Stop minimising and send full query when
2732 * RCODE is not NOERROR. */
2733 iq->minimisation_state = DONOT_MINIMISE_STATE;
2735 if(FLAGS_GET_RCODE(iq->response->rep->flags) ==
2736 LDNS_RCODE_NXDOMAIN) {
2737 /* Stop resolving when NXDOMAIN is DNSSEC
2738 * signed. Based on assumption that nameservers
2739 * serving signed zones do not return NXDOMAIN
2740 * for empty-non-terminals. */
2741 if(iq->dnssec_expected)
2742 return final_state(iq);
2743 /* Make subrequest to validate intermediate
2744 * NXDOMAIN if harden-below-nxdomain is
2746 if(qstate->env->cfg->harden_below_nxdomain) {
2747 struct module_qstate* subq = NULL;
2748 log_query_info(VERB_QUERY,
2749 "schedule NXDOMAIN validation:",
2750 &iq->response->qinfo);
2751 if(!generate_sub_request(
2752 iq->response->qinfo.qname,
2753 iq->response->qinfo.qname_len,
2754 iq->response->qinfo.qtype,
2755 iq->response->qinfo.qclass,
2758 FINISHED_STATE, &subq, 1))
2760 "could not validate NXDOMAIN "
2762 outbound_list_clear(&iq->outlist);
2763 iq->num_current_queries = 0;
2764 fptr_ok(fptr_whitelist_modenv_detach_subs(
2765 qstate->env->detach_subs));
2766 (*qstate->env->detach_subs)(qstate);
2767 iq->num_target_queries = 0;
2770 return next_state(iq, QUERYTARGETS_STATE);
2772 return final_state(iq);
2773 } else if(type == RESPONSE_TYPE_REFERRAL) {
2774 /* REFERRAL type responses get a reset of the
2775 * delegation point, and back to the QUERYTARGETS_STATE. */
2776 verbose(VERB_DETAIL, "query response was REFERRAL");
2778 if(!(iq->chase_flags & BIT_RD) && !iq->ratelimit_ok) {
2779 /* we have a referral, no ratelimit, we can send
2780 * our queries to the given name */
2781 infra_ratelimit_dec(qstate->env->infra_cache,
2782 iq->dp->name, iq->dp->namelen,
2786 /* if hardened, only store referral if we asked for it */
2787 if(!qstate->no_cache_store &&
2788 (!qstate->env->cfg->harden_referral_path ||
2789 ( qstate->qinfo.qtype == LDNS_RR_TYPE_NS
2790 && (qstate->query_flags&BIT_RD)
2791 && !(qstate->query_flags&BIT_CD)
2792 /* we know that all other NS rrsets are scrubbed
2793 * away, thus on referral only one is left.
2794 * see if that equals the query name... */
2795 && ( /* auth section, but sometimes in answer section*/
2796 reply_find_rrset_section_ns(iq->response->rep,
2797 iq->qchase.qname, iq->qchase.qname_len,
2798 LDNS_RR_TYPE_NS, iq->qchase.qclass)
2799 || reply_find_rrset_section_an(iq->response->rep,
2800 iq->qchase.qname, iq->qchase.qname_len,
2801 LDNS_RR_TYPE_NS, iq->qchase.qclass)
2804 /* Store the referral under the current query */
2805 /* no prefetch-leeway, since its not the answer */
2806 iter_dns_store(qstate->env, &iq->response->qinfo,
2807 iq->response->rep, 1, 0, 0, NULL, 0);
2808 if(iq->store_parent_NS)
2809 iter_store_parentside_NS(qstate->env,
2811 if(qstate->env->neg_cache)
2812 val_neg_addreferral(qstate->env->neg_cache,
2813 iq->response->rep, iq->dp->name);
2815 /* store parent-side-in-zone-glue, if directly queried for */
2816 if(!qstate->no_cache_store && iq->query_for_pside_glue
2817 && !iq->pside_glue) {
2818 iq->pside_glue = reply_find_rrset(iq->response->rep,
2819 iq->qchase.qname, iq->qchase.qname_len,
2820 iq->qchase.qtype, iq->qchase.qclass);
2821 if(iq->pside_glue) {
2822 log_rrset_key(VERB_ALGO, "found parent-side "
2823 "glue", iq->pside_glue);
2824 iter_store_parentside_rrset(qstate->env,
2829 /* Reset the event state, setting the current delegation
2830 * point to the referral. */
2831 iq->deleg_msg = iq->response;
2832 iq->dp = delegpt_from_message(iq->response, qstate->region);
2833 if (qstate->env->cfg->qname_minimisation)
2834 iq->minimisation_state = INIT_MINIMISE_STATE;
2836 errinf(qstate, "malloc failure, for delegation point");
2837 return error_response(qstate, id, LDNS_RCODE_SERVFAIL);
2839 if(!cache_fill_missing(qstate->env, iq->qchase.qclass,
2840 qstate->region, iq->dp)) {
2841 errinf(qstate, "malloc failure, copy extra info into delegation point");
2842 return error_response(qstate, id, LDNS_RCODE_SERVFAIL);
2844 if(iq->store_parent_NS && query_dname_compare(iq->dp->name,
2845 iq->store_parent_NS->name) == 0)
2846 iter_merge_retry_counts(iq->dp, iq->store_parent_NS);
2847 delegpt_log(VERB_ALGO, iq->dp);
2848 /* Count this as a referral. */
2849 iq->referral_count++;
2851 /* see if the next dp is a trust anchor, or a DS was sent
2852 * along, indicating dnssec is expected for next zone */
2853 iq->dnssec_expected = iter_indicates_dnssec(qstate->env,
2854 iq->dp, iq->response, iq->qchase.qclass);
2855 /* if dnssec, validating then also fetch the key for the DS */
2856 if(iq->dnssec_expected && qstate->env->cfg->prefetch_key &&
2857 !(qstate->query_flags&BIT_CD))
2858 generate_dnskey_prefetch(qstate, iq, id);
2860 /* spawn off NS and addr to auth servers for the NS we just
2861 * got in the referral. This gets authoritative answer
2862 * (answer section trust level) rrset.
2863 * right after, we detach the subs, answer goes to cache. */
2864 if(qstate->env->cfg->harden_referral_path)
2865 generate_ns_check(qstate, iq, id);
2867 /* stop current outstanding queries.
2868 * FIXME: should the outstanding queries be waited for and
2869 * handled? Say by a subquery that inherits the outbound_entry.
2871 outbound_list_clear(&iq->outlist);
2872 iq->num_current_queries = 0;
2873 fptr_ok(fptr_whitelist_modenv_detach_subs(
2874 qstate->env->detach_subs));
2875 (*qstate->env->detach_subs)(qstate);
2876 iq->num_target_queries = 0;
2877 verbose(VERB_ALGO, "cleared outbound list for next round");
2878 return next_state(iq, QUERYTARGETS_STATE);
2879 } else if(type == RESPONSE_TYPE_CNAME) {
2880 uint8_t* sname = NULL;
2881 size_t snamelen = 0;
2882 /* CNAME type responses get a query restart (i.e., get a
2883 * reset of the query state and go back to INIT_REQUEST_STATE).
2885 verbose(VERB_DETAIL, "query response was CNAME");
2886 if(verbosity >= VERB_ALGO)
2887 log_dns_msg("cname msg", &iq->response->qinfo,
2889 /* if qtype is DS, check we have the right level of answer,
2890 * like grandchild answer but we need the middle, reject it */
2891 if(iq->qchase.qtype == LDNS_RR_TYPE_DS && !iq->dsns_point
2892 && !(iq->chase_flags&BIT_RD)
2893 && iter_ds_toolow(iq->response, iq->dp)
2894 && iter_dp_cangodown(&iq->qchase, iq->dp)) {
2895 outbound_list_clear(&iq->outlist);
2896 iq->num_current_queries = 0;
2897 fptr_ok(fptr_whitelist_modenv_detach_subs(
2898 qstate->env->detach_subs));
2899 (*qstate->env->detach_subs)(qstate);
2900 iq->num_target_queries = 0;
2901 return processDSNSFind(qstate, iq, id);
2903 /* Process the CNAME response. */
2904 if(!handle_cname_response(qstate, iq, iq->response,
2905 &sname, &snamelen)) {
2906 errinf(qstate, "malloc failure, CNAME info");
2907 return error_response(qstate, id, LDNS_RCODE_SERVFAIL);
2909 /* cache the CNAME response under the current query */
2910 /* NOTE : set referral=1, so that rrsets get stored but not
2911 * the partial query answer (CNAME only). */
2912 /* prefetchleeway applied because this updates answer parts */
2913 if(!qstate->no_cache_store)
2914 iter_dns_store(qstate->env, &iq->response->qinfo,
2915 iq->response->rep, 1, qstate->prefetch_leeway,
2916 iq->dp&&iq->dp->has_parent_side_NS, NULL,
2917 qstate->query_flags);
2918 /* set the current request's qname to the new value. */
2919 iq->qchase.qname = sname;
2920 iq->qchase.qname_len = snamelen;
2921 /* Clear the query state, since this is a query restart. */
2922 iq->deleg_msg = NULL;
2924 iq->dsns_point = NULL;
2925 iq->auth_zone_response = 0;
2927 if(iq->minimisation_state != MINIMISE_STATE)
2928 /* Only count as query restart when it is not an extra
2929 * query as result of qname minimisation. */
2930 iq->query_restart_count++;
2931 if(qstate->env->cfg->qname_minimisation)
2932 iq->minimisation_state = INIT_MINIMISE_STATE;
2934 /* stop current outstanding queries.
2935 * FIXME: should the outstanding queries be waited for and
2936 * handled? Say by a subquery that inherits the outbound_entry.
2938 outbound_list_clear(&iq->outlist);
2939 iq->num_current_queries = 0;
2940 fptr_ok(fptr_whitelist_modenv_detach_subs(
2941 qstate->env->detach_subs));
2942 (*qstate->env->detach_subs)(qstate);
2943 iq->num_target_queries = 0;
2945 sock_list_insert(&qstate->reply_origin,
2946 &qstate->reply->addr, qstate->reply->addrlen,
2948 verbose(VERB_ALGO, "cleared outbound list for query restart");
2949 /* go to INIT_REQUEST_STATE for new qname. */
2950 return next_state(iq, INIT_REQUEST_STATE);
2951 } else if(type == RESPONSE_TYPE_LAME) {
2952 /* Cache the LAMEness. */
2953 verbose(VERB_DETAIL, "query response was %sLAME",
2954 dnsseclame?"DNSSEC ":"");
2955 if(!dname_subdomain_c(iq->qchase.qname, iq->dp->name)) {
2956 log_err("mark lame: mismatch in qname and dpname");
2957 /* throwaway this reply below */
2958 } else if(qstate->reply) {
2959 /* need addr for lameness cache, but we may have
2960 * gotten this from cache, so test to be sure */
2961 if(!infra_set_lame(qstate->env->infra_cache,
2962 &qstate->reply->addr, qstate->reply->addrlen,
2963 iq->dp->name, iq->dp->namelen,
2964 *qstate->env->now, dnsseclame, 0,
2966 log_err("mark host lame: out of memory");
2968 } else if(type == RESPONSE_TYPE_REC_LAME) {
2969 /* Cache the LAMEness. */
2970 verbose(VERB_DETAIL, "query response REC_LAME: "
2971 "recursive but not authoritative server");
2972 if(!dname_subdomain_c(iq->qchase.qname, iq->dp->name)) {
2973 log_err("mark rec_lame: mismatch in qname and dpname");
2974 /* throwaway this reply below */
2975 } else if(qstate->reply) {
2976 /* need addr for lameness cache, but we may have
2977 * gotten this from cache, so test to be sure */
2978 verbose(VERB_DETAIL, "mark as REC_LAME");
2979 if(!infra_set_lame(qstate->env->infra_cache,
2980 &qstate->reply->addr, qstate->reply->addrlen,
2981 iq->dp->name, iq->dp->namelen,
2982 *qstate->env->now, 0, 1, iq->qchase.qtype))
2983 log_err("mark host lame: out of memory");
2985 } else if(type == RESPONSE_TYPE_THROWAWAY) {
2986 /* LAME and THROWAWAY responses are handled the same way.
2987 * In this case, the event is just sent directly back to
2988 * the QUERYTARGETS_STATE without resetting anything,
2989 * because, clearly, the next target must be tried. */
2990 verbose(VERB_DETAIL, "query response was THROWAWAY");
2992 log_warn("A query response came back with an unknown type: %d",
2996 /* LAME, THROWAWAY and "unknown" all end up here.
2997 * Recycle to the QUERYTARGETS state to hopefully try a
2998 * different target. */
2999 if (qstate->env->cfg->qname_minimisation &&
3000 !qstate->env->cfg->qname_minimisation_strict)
3001 iq->minimisation_state = DONOT_MINIMISE_STATE;
3002 if(iq->auth_zone_response) {
3003 /* can we fallback? */
3004 iq->auth_zone_response = 0;
3005 if(!auth_zones_can_fallback(qstate->env->auth_zones,
3006 iq->dp->name, iq->dp->namelen, qstate->qinfo.qclass)) {
3007 verbose(VERB_ALGO, "auth zone response bad, and no"
3008 " fallback possible, servfail");
3009 errinf_dname(qstate, "response is bad, no fallback, "
3010 "for auth zone", iq->dp->name);
3011 return error_response(qstate, id, LDNS_RCODE_SERVFAIL);
3013 verbose(VERB_ALGO, "auth zone response was bad, "
3014 "fallback enabled");
3015 iq->auth_zone_avoid = 1;
3016 if(iq->dp->auth_dp) {
3017 /* we are using a dp for the auth zone, with no
3018 * nameservers, get one first */
3020 return next_state(iq, INIT_REQUEST_STATE);
3023 return next_state(iq, QUERYTARGETS_STATE);
3027 * Return priming query results to interested super querystates.
3029 * Sets the delegation point and delegation message (not nonRD queries).
3030 * This is a callback from walk_supers.
3032 * @param qstate: priming query state that finished.
3033 * @param id: module id.
3034 * @param forq: the qstate for which priming has been done.
3037 prime_supers(struct module_qstate* qstate, int id, struct module_qstate* forq)
3039 struct iter_qstate* foriq = (struct iter_qstate*)forq->minfo[id];
3040 struct delegpt* dp = NULL;
3042 log_assert(qstate->is_priming || foriq->wait_priming_stub);
3043 log_assert(qstate->return_rcode == LDNS_RCODE_NOERROR);
3044 /* Convert our response to a delegation point */
3045 dp = delegpt_from_message(qstate->return_msg, forq->region);
3047 /* if there is no convertable delegation point, then
3048 * the ANSWER type was (presumably) a negative answer. */
3049 verbose(VERB_ALGO, "prime response was not a positive "
3052 foriq->state = QUERYTARGETS_STATE;
3056 log_query_info(VERB_DETAIL, "priming successful for", &qstate->qinfo);
3057 delegpt_log(VERB_ALGO, dp);
3059 foriq->deleg_msg = dns_copy_msg(qstate->return_msg, forq->region);
3060 if(!foriq->deleg_msg) {
3061 log_err("copy prime response: out of memory");
3063 foriq->state = QUERYTARGETS_STATE;
3067 /* root priming responses go to init stage 2, priming stub
3068 * responses to to stage 3. */
3069 if(foriq->wait_priming_stub) {
3070 foriq->state = INIT_REQUEST_3_STATE;
3071 foriq->wait_priming_stub = 0;
3072 } else foriq->state = INIT_REQUEST_2_STATE;
3073 /* because we are finished, the parent will be reactivated */
3077 * This handles the response to a priming query. This is used to handle both
3078 * root and stub priming responses. This is basically the equivalent of the
3079 * QUERY_RESP_STATE, but will not handle CNAME responses and will treat
3080 * REFERRALs as ANSWERS. It will also update and reactivate the originating
3083 * @param qstate: query state.
3084 * @param id: module id.
3085 * @return true if the event needs more immediate processing, false if not.
3086 * This state always returns false.
3089 processPrimeResponse(struct module_qstate* qstate, int id)
3091 struct iter_qstate* iq = (struct iter_qstate*)qstate->minfo[id];
3092 enum response_type type;
3093 iq->response->rep->flags &= ~(BIT_RD|BIT_RA); /* ignore rec-lame */
3094 type = response_type_from_server(
3095 (int)((iq->chase_flags&BIT_RD) || iq->chase_to_rd),
3096 iq->response, &iq->qchase, iq->dp);
3097 if(type == RESPONSE_TYPE_ANSWER) {
3098 qstate->return_rcode = LDNS_RCODE_NOERROR;
3099 qstate->return_msg = iq->response;
3101 errinf(qstate, "prime response did not get an answer");
3102 errinf_dname(qstate, "for", qstate->qinfo.qname);
3103 qstate->return_rcode = LDNS_RCODE_SERVFAIL;
3104 qstate->return_msg = NULL;
3107 /* validate the root or stub after priming (if enabled).
3108 * This is the same query as the prime query, but with validation.
3109 * Now that we are primed, the additional queries that validation
3110 * may need can be resolved, such as DLV. */
3111 if(qstate->env->cfg->harden_referral_path) {
3112 struct module_qstate* subq = NULL;
3113 log_nametypeclass(VERB_ALGO, "schedule prime validation",
3114 qstate->qinfo.qname, qstate->qinfo.qtype,
3115 qstate->qinfo.qclass);
3116 if(!generate_sub_request(qstate->qinfo.qname,
3117 qstate->qinfo.qname_len, qstate->qinfo.qtype,
3118 qstate->qinfo.qclass, qstate, id, iq,
3119 INIT_REQUEST_STATE, FINISHED_STATE, &subq, 1)) {
3120 verbose(VERB_ALGO, "could not generate prime check");
3122 generate_a_aaaa_check(qstate, iq, id);
3125 /* This event is finished. */
3126 qstate->ext_state[id] = module_finished;
3131 * Do final processing on responses to target queries. Events reach this
3132 * state after the iterative resolution algorithm terminates. This state is
3133 * responsible for reactivating the original event, and housekeeping related
3134 * to received target responses (caching, updating the current delegation
3136 * Callback from walk_supers for every super state that is interested in
3137 * the results from this query.
3139 * @param qstate: query state.
3140 * @param id: module id.
3141 * @param forq: super query state.
3144 processTargetResponse(struct module_qstate* qstate, int id,
3145 struct module_qstate* forq)
3147 struct iter_qstate* iq = (struct iter_qstate*)qstate->minfo[id];
3148 struct iter_qstate* foriq = (struct iter_qstate*)forq->minfo[id];
3149 struct ub_packed_rrset_key* rrset;
3150 struct delegpt_ns* dpns;
3151 log_assert(qstate->return_rcode == LDNS_RCODE_NOERROR);
3153 foriq->state = QUERYTARGETS_STATE;
3154 log_query_info(VERB_ALGO, "processTargetResponse", &qstate->qinfo);
3155 log_query_info(VERB_ALGO, "processTargetResponse super", &forq->qinfo);
3157 /* Tell the originating event that this target query has finished
3158 * (regardless if it succeeded or not). */
3159 foriq->num_target_queries--;
3161 /* check to see if parent event is still interested (in orig name). */
3163 verbose(VERB_ALGO, "subq: parent not interested, was reset");
3164 return; /* not interested anymore */
3166 dpns = delegpt_find_ns(foriq->dp, qstate->qinfo.qname,
3167 qstate->qinfo.qname_len);
3169 /* If not interested, just stop processing this event */
3170 verbose(VERB_ALGO, "subq: parent not interested anymore");
3171 /* could be because parent was jostled out of the cache,
3172 and a new identical query arrived, that does not want it*/
3176 /* if iq->query_for_pside_glue then add the pside_glue (marked lame) */
3177 if(iq->pside_glue) {
3178 /* if the pside_glue is NULL, then it could not be found,
3179 * the done_pside is already set when created and a cache
3180 * entry created in processFinished so nothing to do here */
3181 log_rrset_key(VERB_ALGO, "add parentside glue to dp",
3183 if(!delegpt_add_rrset(foriq->dp, forq->region,
3185 log_err("out of memory adding pside glue");
3188 /* This response is relevant to the current query, so we
3189 * add (attempt to add, anyway) this target(s) and reactivate
3190 * the original event.
3191 * NOTE: we could only look for the AnswerRRset if the
3192 * response type was ANSWER. */
3193 rrset = reply_find_answer_rrset(&iq->qchase, qstate->return_msg->rep);
3195 /* if CNAMEs have been followed - add new NS to delegpt. */
3196 /* BTW. RFC 1918 says NS should not have got CNAMEs. Robust. */
3197 if(!delegpt_find_ns(foriq->dp, rrset->rk.dname,
3198 rrset->rk.dname_len)) {
3199 /* if dpns->lame then set newcname ns lame too */
3200 if(!delegpt_add_ns(foriq->dp, forq->region,
3201 rrset->rk.dname, dpns->lame))
3202 log_err("out of memory adding cnamed-ns");
3204 /* if dpns->lame then set the address(es) lame too */
3205 if(!delegpt_add_rrset(foriq->dp, forq->region, rrset,
3207 log_err("out of memory adding targets");
3208 verbose(VERB_ALGO, "added target response");
3209 delegpt_log(VERB_ALGO, foriq->dp);
3211 verbose(VERB_ALGO, "iterator TargetResponse failed");
3212 dpns->resolved = 1; /* fail the target */
3217 * Process response for DS NS Find queries, that attempt to find the delegation
3218 * point where we ask the DS query from.
3220 * @param qstate: query state.
3221 * @param id: module id.
3222 * @param forq: super query state.
3225 processDSNSResponse(struct module_qstate* qstate, int id,
3226 struct module_qstate* forq)
3228 struct iter_qstate* foriq = (struct iter_qstate*)forq->minfo[id];
3230 /* if the finished (iq->response) query has no NS set: continue
3231 * up to look for the right dp; nothing to change, do DPNSstate */
3232 if(qstate->return_rcode != LDNS_RCODE_NOERROR)
3233 return; /* seek further */
3234 /* find the NS RRset (without allowing CNAMEs) */
3235 if(!reply_find_rrset(qstate->return_msg->rep, qstate->qinfo.qname,
3236 qstate->qinfo.qname_len, LDNS_RR_TYPE_NS,
3237 qstate->qinfo.qclass)){
3238 return; /* seek further */
3241 /* else, store as DP and continue at querytargets */
3242 foriq->state = QUERYTARGETS_STATE;
3243 foriq->dp = delegpt_from_message(qstate->return_msg, forq->region);
3245 log_err("out of memory in dsns dp alloc");
3246 errinf(qstate, "malloc failure, in DS search");
3247 return; /* dp==NULL in QUERYTARGETS makes SERVFAIL */
3249 /* success, go query the querytargets in the new dp (and go down) */
3253 * Process response for qclass=ANY queries for a particular class.
3254 * Append to result or error-exit.
3256 * @param qstate: query state.
3257 * @param id: module id.
3258 * @param forq: super query state.
3261 processClassResponse(struct module_qstate* qstate, int id,
3262 struct module_qstate* forq)
3264 struct iter_qstate* foriq = (struct iter_qstate*)forq->minfo[id];
3265 struct dns_msg* from = qstate->return_msg;
3266 log_query_info(VERB_ALGO, "processClassResponse", &qstate->qinfo);
3267 log_query_info(VERB_ALGO, "processClassResponse super", &forq->qinfo);
3268 if(qstate->return_rcode != LDNS_RCODE_NOERROR) {
3269 /* cause servfail for qclass ANY query */
3270 foriq->response = NULL;
3271 foriq->state = FINISHED_STATE;
3275 if(!foriq->response) {
3276 /* allocate the response: copy RCODE, sec_state */
3277 foriq->response = dns_copy_msg(from, forq->region);
3278 if(!foriq->response) {
3279 log_err("malloc failed for qclass ANY response");
3280 foriq->state = FINISHED_STATE;
3283 foriq->response->qinfo.qclass = forq->qinfo.qclass;
3284 /* qclass ANY does not receive the AA flag on replies */
3285 foriq->response->rep->authoritative = 0;
3287 struct dns_msg* to = foriq->response;
3288 /* add _from_ this response _to_ existing collection */
3289 /* if there are records, copy RCODE */
3290 /* lower sec_state if this message is lower */
3291 if(from->rep->rrset_count != 0) {
3292 size_t n = from->rep->rrset_count+to->rep->rrset_count;
3293 struct ub_packed_rrset_key** dest, **d;
3294 /* copy appropriate rcode */
3295 to->rep->flags = from->rep->flags;
3297 if(from->rep->rrset_count > RR_COUNT_MAX ||
3298 to->rep->rrset_count > RR_COUNT_MAX) {
3299 log_err("malloc failed (too many rrsets) in collect ANY");
3300 foriq->state = FINISHED_STATE;
3301 return; /* integer overflow protection */
3303 dest = regional_alloc(forq->region, sizeof(dest[0])*n);
3305 log_err("malloc failed in collect ANY");
3306 foriq->state = FINISHED_STATE;
3311 memcpy(dest, to->rep->rrsets, to->rep->an_numrrsets
3313 dest += to->rep->an_numrrsets;
3314 memcpy(dest, from->rep->rrsets, from->rep->an_numrrsets
3316 dest += from->rep->an_numrrsets;
3318 memcpy(dest, to->rep->rrsets+to->rep->an_numrrsets,
3319 to->rep->ns_numrrsets * sizeof(dest[0]));
3320 dest += to->rep->ns_numrrsets;
3321 memcpy(dest, from->rep->rrsets+from->rep->an_numrrsets,
3322 from->rep->ns_numrrsets * sizeof(dest[0]));
3323 dest += from->rep->ns_numrrsets;
3325 memcpy(dest, to->rep->rrsets+to->rep->an_numrrsets+
3326 to->rep->ns_numrrsets,
3327 to->rep->ar_numrrsets * sizeof(dest[0]));
3328 dest += to->rep->ar_numrrsets;
3329 memcpy(dest, from->rep->rrsets+from->rep->an_numrrsets+
3330 from->rep->ns_numrrsets,
3331 from->rep->ar_numrrsets * sizeof(dest[0]));
3333 to->rep->rrsets = d;
3334 to->rep->an_numrrsets += from->rep->an_numrrsets;
3335 to->rep->ns_numrrsets += from->rep->ns_numrrsets;
3336 to->rep->ar_numrrsets += from->rep->ar_numrrsets;
3337 to->rep->rrset_count = n;
3339 if(from->rep->security < to->rep->security) /* lowest sec */
3340 to->rep->security = from->rep->security;
3341 if(from->rep->qdcount != 0) /* insert qd if appropriate */
3342 to->rep->qdcount = from->rep->qdcount;
3343 if(from->rep->ttl < to->rep->ttl) /* use smallest TTL */
3344 to->rep->ttl = from->rep->ttl;
3345 if(from->rep->prefetch_ttl < to->rep->prefetch_ttl)
3346 to->rep->prefetch_ttl = from->rep->prefetch_ttl;
3347 if(from->rep->serve_expired_ttl < to->rep->serve_expired_ttl)
3348 to->rep->serve_expired_ttl = from->rep->serve_expired_ttl;
3351 foriq->num_current_queries --;
3352 if(foriq->num_current_queries == 0)
3353 foriq->state = FINISHED_STATE;
3357 * Collect class ANY responses and make them into one response. This
3358 * state is started and it creates queries for all classes (that have
3359 * root hints). The answers are then collected.
3361 * @param qstate: query state.
3362 * @param id: module id.
3363 * @return true if the event needs more immediate processing, false if not.
3366 processCollectClass(struct module_qstate* qstate, int id)
3368 struct iter_qstate* iq = (struct iter_qstate*)qstate->minfo[id];
3369 struct module_qstate* subq;
3370 /* If qchase.qclass == 0 then send out queries for all classes.
3371 * Otherwise, do nothing (wait for all answers to arrive and the
3372 * processClassResponse to put them together, and that moves us
3373 * towards the Finished state when done. */
3374 if(iq->qchase.qclass == 0) {
3376 iq->qchase.qclass = LDNS_RR_CLASS_ANY;
3377 while(iter_get_next_root(qstate->env->hints,
3378 qstate->env->fwds, &c)) {
3379 /* generate query for this class */
3380 log_nametypeclass(VERB_ALGO, "spawn collect query",
3381 qstate->qinfo.qname, qstate->qinfo.qtype, c);
3382 if(!generate_sub_request(qstate->qinfo.qname,
3383 qstate->qinfo.qname_len, qstate->qinfo.qtype,
3384 c, qstate, id, iq, INIT_REQUEST_STATE,
3385 FINISHED_STATE, &subq,
3386 (int)!(qstate->query_flags&BIT_CD))) {
3387 errinf(qstate, "could not generate class ANY"
3389 return error_response(qstate, id,
3390 LDNS_RCODE_SERVFAIL);
3392 /* ignore subq, no special init required */
3393 iq->num_current_queries ++;
3398 /* if no roots are configured at all, return */
3399 if(iq->num_current_queries == 0) {
3400 verbose(VERB_ALGO, "No root hints or fwds, giving up "
3402 return error_response(qstate, id, LDNS_RCODE_REFUSED);
3404 /* return false, wait for queries to return */
3406 /* if woke up here because of an answer, wait for more answers */
3411 * This handles the final state for first-tier responses (i.e., responses to
3412 * externally generated queries).
3414 * @param qstate: query state.
3415 * @param iq: iterator query state.
3416 * @param id: module id.
3417 * @return true if the event needs more processing, false if not. Since this
3418 * is the final state for an event, it always returns false.
3421 processFinished(struct module_qstate* qstate, struct iter_qstate* iq,
3424 log_query_info(VERB_QUERY, "finishing processing for",
3427 /* store negative cache element for parent side glue. */
3428 if(!qstate->no_cache_store && iq->query_for_pside_glue
3430 iter_store_parentside_neg(qstate->env, &qstate->qinfo,
3431 iq->deleg_msg?iq->deleg_msg->rep:
3432 (iq->response?iq->response->rep:NULL));
3434 verbose(VERB_ALGO, "No response is set, servfail");
3435 errinf(qstate, "(no response found at query finish)");
3436 return error_response(qstate, id, LDNS_RCODE_SERVFAIL);
3439 /* Make sure that the RA flag is set (since the presence of
3440 * this module means that recursion is available) */
3441 iq->response->rep->flags |= BIT_RA;
3443 /* Clear the AA flag */
3444 /* FIXME: does this action go here or in some other module? */
3445 iq->response->rep->flags &= ~BIT_AA;
3447 /* make sure QR flag is on */
3448 iq->response->rep->flags |= BIT_QR;
3450 /* we have finished processing this query */
3451 qstate->ext_state[id] = module_finished;
3453 /* TODO: we are using a private TTL, trim the response. */
3454 /* if (mPrivateTTL > 0){IterUtils.setPrivateTTL(resp, mPrivateTTL); } */
3456 /* prepend any items we have accumulated */
3457 if(iq->an_prepend_list || iq->ns_prepend_list) {
3458 if(!iter_prepend(iq, iq->response, qstate->region)) {
3459 log_err("prepend rrsets: out of memory");
3460 return error_response(qstate, id, LDNS_RCODE_SERVFAIL);
3462 /* reset the query name back */
3463 iq->response->qinfo = qstate->qinfo;
3464 /* the security state depends on the combination */
3465 iq->response->rep->security = sec_status_unchecked;
3466 /* store message with the finished prepended items,
3467 * but only if we did recursion. The nonrecursion referral
3468 * from cache does not need to be stored in the msg cache. */
3469 if(!qstate->no_cache_store && qstate->query_flags&BIT_RD) {
3470 iter_dns_store(qstate->env, &qstate->qinfo,
3471 iq->response->rep, 0, qstate->prefetch_leeway,
3472 iq->dp&&iq->dp->has_parent_side_NS,
3473 qstate->region, qstate->query_flags);
3476 qstate->return_rcode = LDNS_RCODE_NOERROR;
3477 qstate->return_msg = iq->response;
3482 * Return priming query results to interested super querystates.
3484 * Sets the delegation point and delegation message (not nonRD queries).
3485 * This is a callback from walk_supers.
3487 * @param qstate: query state that finished.
3488 * @param id: module id.
3489 * @param super: the qstate to inform.
3492 iter_inform_super(struct module_qstate* qstate, int id,
3493 struct module_qstate* super)
3495 if(!qstate->is_priming && super->qinfo.qclass == LDNS_RR_CLASS_ANY)
3496 processClassResponse(qstate, id, super);
3497 else if(super->qinfo.qtype == LDNS_RR_TYPE_DS && ((struct iter_qstate*)
3498 super->minfo[id])->state == DSNS_FIND_STATE)
3499 processDSNSResponse(qstate, id, super);
3500 else if(qstate->return_rcode != LDNS_RCODE_NOERROR)
3501 error_supers(qstate, id, super);
3502 else if(qstate->is_priming)
3503 prime_supers(qstate, id, super);
3504 else processTargetResponse(qstate, id, super);
3508 * Handle iterator state.
3509 * Handle events. This is the real processing loop for events, responsible
3510 * for moving events through the various states. If a processing method
3511 * returns true, then it will be advanced to the next state. If false, then
3512 * processing will stop.
3514 * @param qstate: query state.
3515 * @param ie: iterator shared global environment.
3516 * @param iq: iterator query state.
3517 * @param id: module id.
3520 iter_handle(struct module_qstate* qstate, struct iter_qstate* iq,
3521 struct iter_env* ie, int id)
3525 verbose(VERB_ALGO, "iter_handle processing q with state %s",
3526 iter_state_to_string(iq->state));
3528 case INIT_REQUEST_STATE:
3529 cont = processInitRequest(qstate, iq, ie, id);
3531 case INIT_REQUEST_2_STATE:
3532 cont = processInitRequest2(qstate, iq, id);
3534 case INIT_REQUEST_3_STATE:
3535 cont = processInitRequest3(qstate, iq, id);
3537 case QUERYTARGETS_STATE:
3538 cont = processQueryTargets(qstate, iq, ie, id);
3540 case QUERY_RESP_STATE:
3541 cont = processQueryResponse(qstate, iq, id);
3543 case PRIME_RESP_STATE:
3544 cont = processPrimeResponse(qstate, id);
3546 case COLLECT_CLASS_STATE:
3547 cont = processCollectClass(qstate, id);
3549 case DSNS_FIND_STATE:
3550 cont = processDSNSFind(qstate, iq, id);
3552 case FINISHED_STATE:
3553 cont = processFinished(qstate, iq, id);
3556 log_warn("iterator: invalid state: %d",
3565 * This is the primary entry point for processing request events. Note that
3566 * this method should only be used by external modules.
3567 * @param qstate: query state.
3568 * @param ie: iterator shared global environment.
3569 * @param iq: iterator query state.
3570 * @param id: module id.
3573 process_request(struct module_qstate* qstate, struct iter_qstate* iq,
3574 struct iter_env* ie, int id)
3576 /* external requests start in the INIT state, and finish using the
3577 * FINISHED state. */
3578 iq->state = INIT_REQUEST_STATE;
3579 iq->final_state = FINISHED_STATE;
3580 verbose(VERB_ALGO, "process_request: new external request event");
3581 iter_handle(qstate, iq, ie, id);
3584 /** process authoritative server reply */
3586 process_response(struct module_qstate* qstate, struct iter_qstate* iq,
3587 struct iter_env* ie, int id, struct outbound_entry* outbound,
3588 enum module_ev event)
3590 struct msg_parse* prs;
3591 struct edns_data edns;
3594 verbose(VERB_ALGO, "process_response: new external response event");
3595 iq->response = NULL;
3596 iq->state = QUERY_RESP_STATE;
3597 if(event == module_event_noreply || event == module_event_error) {
3598 if(event == module_event_noreply && iq->sent_count >= 3 &&
3599 qstate->env->cfg->use_caps_bits_for_id &&
3600 !iq->caps_fallback && !is_caps_whitelisted(ie, iq)) {
3601 /* start fallback */
3602 iq->caps_fallback = 1;
3603 iq->caps_server = 0;
3604 iq->caps_reply = NULL;
3605 iq->caps_response = NULL;
3606 iq->caps_minimisation_state = DONOT_MINIMISE_STATE;
3607 iq->state = QUERYTARGETS_STATE;
3608 iq->num_current_queries--;
3609 /* need fresh attempts for the 0x20 fallback, if
3610 * that was the cause for the failure */
3611 iter_dec_attempts(iq->dp, 3);
3612 verbose(VERB_DETAIL, "Capsforid: timeouts, starting fallback");
3617 if( (event != module_event_reply && event != module_event_capsfail)
3618 || !qstate->reply) {
3619 log_err("Bad event combined with response");
3620 outbound_list_remove(&iq->outlist, outbound);
3621 errinf(qstate, "module iterator received wrong internal event with a response message");
3622 (void)error_response(qstate, id, LDNS_RCODE_SERVFAIL);
3627 prs = (struct msg_parse*)regional_alloc(qstate->env->scratch,
3628 sizeof(struct msg_parse));
3630 log_err("out of memory on incoming message");
3631 /* like packet got dropped */
3634 memset(prs, 0, sizeof(*prs));
3635 memset(&edns, 0, sizeof(edns));
3636 pkt = qstate->reply->c->buffer;
3637 sldns_buffer_set_position(pkt, 0);
3638 if(parse_packet(pkt, prs, qstate->env->scratch) != LDNS_RCODE_NOERROR) {
3639 verbose(VERB_ALGO, "parse error on reply packet");
3642 /* edns is not examined, but removed from message to help cache */
3643 if(parse_extract_edns(prs, &edns, qstate->env->scratch) !=
3647 /* Copy the edns options we may got from the back end */
3649 qstate->edns_opts_back_in = edns_opt_copy_region(edns.opt_list,
3651 if(!qstate->edns_opts_back_in) {
3652 log_err("out of memory on incoming message");
3653 /* like packet got dropped */
3656 if(!inplace_cb_edns_back_parsed_call(qstate->env, qstate)) {
3657 log_err("unable to call edns_back_parsed callback");
3662 /* remove CD-bit, we asked for in case we handle validation ourself */
3663 prs->flags &= ~BIT_CD;
3665 /* normalize and sanitize: easy to delete items from linked lists */
3666 if(!scrub_message(pkt, prs, &iq->qinfo_out, iq->dp->name,
3667 qstate->env->scratch, qstate->env, ie)) {
3668 /* if 0x20 enabled, start fallback, but we have no message */
3669 if(event == module_event_capsfail && !iq->caps_fallback) {
3670 iq->caps_fallback = 1;
3671 iq->caps_server = 0;
3672 iq->caps_reply = NULL;
3673 iq->caps_response = NULL;
3674 iq->caps_minimisation_state = DONOT_MINIMISE_STATE;
3675 iq->state = QUERYTARGETS_STATE;
3676 iq->num_current_queries--;
3677 verbose(VERB_DETAIL, "Capsforid: scrub failed, starting fallback with no response");
3682 /* allocate response dns_msg in region */
3683 iq->response = dns_alloc_msg(pkt, prs, qstate->region);
3686 log_query_info(VERB_DETAIL, "response for", &qstate->qinfo);
3687 log_name_addr(VERB_DETAIL, "reply from", iq->dp->name,
3688 &qstate->reply->addr, qstate->reply->addrlen);
3689 if(verbosity >= VERB_ALGO)
3690 log_dns_msg("incoming scrubbed packet:", &iq->response->qinfo,
3693 if(event == module_event_capsfail || iq->caps_fallback) {
3694 if(qstate->env->cfg->qname_minimisation &&
3695 iq->minimisation_state != DONOT_MINIMISE_STATE) {
3696 /* Skip QNAME minimisation for next query, since that
3697 * one has to match the current query. */
3698 iq->minimisation_state = SKIP_MINIMISE_STATE;
3700 /* for fallback we care about main answer, not additionals */
3701 /* removing that makes comparison more likely to succeed */
3702 caps_strip_reply(iq->response->rep);
3704 if(iq->caps_fallback &&
3705 iq->caps_minimisation_state != iq->minimisation_state) {
3706 /* QNAME minimisation state has changed, restart caps
3708 iq->caps_fallback = 0;
3711 if(!iq->caps_fallback) {
3712 /* start fallback */
3713 iq->caps_fallback = 1;
3714 iq->caps_server = 0;
3715 iq->caps_reply = iq->response->rep;
3716 iq->caps_response = iq->response;
3717 iq->caps_minimisation_state = iq->minimisation_state;
3718 iq->state = QUERYTARGETS_STATE;
3719 iq->num_current_queries--;
3720 verbose(VERB_DETAIL, "Capsforid: starting fallback");
3723 /* check if reply is the same, otherwise, fail */
3724 if(!iq->caps_reply) {
3725 iq->caps_reply = iq->response->rep;
3726 iq->caps_response = iq->response;
3727 iq->caps_server = -1; /*become zero at ++,
3728 so that we start the full set of trials */
3729 } else if(caps_failed_rcode(iq->caps_reply) &&
3730 !caps_failed_rcode(iq->response->rep)) {
3731 /* prefer to upgrade to non-SERVFAIL */
3732 iq->caps_reply = iq->response->rep;
3733 iq->caps_response = iq->response;
3734 } else if(!caps_failed_rcode(iq->caps_reply) &&
3735 caps_failed_rcode(iq->response->rep)) {
3736 /* if we have non-SERVFAIL as answer then
3737 * we can ignore SERVFAILs for the equality
3739 /* no instructions here, skip other else */
3740 } else if(caps_failed_rcode(iq->caps_reply) &&
3741 caps_failed_rcode(iq->response->rep)) {
3742 /* failure is same as other failure in fallbk*/
3743 /* no instructions here, skip other else */
3744 } else if(!reply_equal(iq->response->rep, iq->caps_reply,
3745 qstate->env->scratch)) {
3746 verbose(VERB_DETAIL, "Capsforid fallback: "
3747 "getting different replies, failed");
3748 outbound_list_remove(&iq->outlist, outbound);
3749 errinf(qstate, "0x20 failed, then got different replies in fallback");
3750 (void)error_response(qstate, id,
3751 LDNS_RCODE_SERVFAIL);
3754 /* continue the fallback procedure at next server */
3756 iq->state = QUERYTARGETS_STATE;
3757 iq->num_current_queries--;
3758 verbose(VERB_DETAIL, "Capsforid: reply is equal. "
3759 "go to next fallback");
3763 iq->caps_fallback = 0; /* if we were in fallback, 0x20 is OK now */
3766 outbound_list_remove(&iq->outlist, outbound);
3767 iter_handle(qstate, iq, ie, id);
3771 iter_operate(struct module_qstate* qstate, enum module_ev event, int id,
3772 struct outbound_entry* outbound)
3774 struct iter_env* ie = (struct iter_env*)qstate->env->modinfo[id];
3775 struct iter_qstate* iq = (struct iter_qstate*)qstate->minfo[id];
3776 verbose(VERB_QUERY, "iterator[module %d] operate: extstate:%s event:%s",
3777 id, strextstate(qstate->ext_state[id]), strmodulevent(event));
3778 if(iq) log_query_info(VERB_QUERY, "iterator operate: query",
3780 if(iq && qstate->qinfo.qname != iq->qchase.qname)
3781 log_query_info(VERB_QUERY, "iterator operate: chased to",
3784 /* perform iterator state machine */
3785 if((event == module_event_new || event == module_event_pass) &&
3787 if(!iter_new(qstate, id)) {
3788 errinf(qstate, "malloc failure, new iterator module allocation");
3789 (void)error_response(qstate, id, LDNS_RCODE_SERVFAIL);
3792 iq = (struct iter_qstate*)qstate->minfo[id];
3793 process_request(qstate, iq, ie, id);
3796 if(iq && event == module_event_pass) {
3797 iter_handle(qstate, iq, ie, id);
3800 if(iq && outbound) {
3801 process_response(qstate, iq, ie, id, outbound, event);
3804 if(event == module_event_error) {
3805 verbose(VERB_ALGO, "got called with event error, giving up");
3806 errinf(qstate, "iterator module got the error event");
3807 (void)error_response(qstate, id, LDNS_RCODE_SERVFAIL);
3811 log_err("bad event for iterator");
3812 errinf(qstate, "iterator module received wrong event");
3813 (void)error_response(qstate, id, LDNS_RCODE_SERVFAIL);
3817 iter_clear(struct module_qstate* qstate, int id)
3819 struct iter_qstate* iq;
3822 iq = (struct iter_qstate*)qstate->minfo[id];
3824 outbound_list_clear(&iq->outlist);
3825 if(iq->target_count && --iq->target_count[0] == 0)
3826 free(iq->target_count);
3827 iq->num_current_queries = 0;
3829 qstate->minfo[id] = NULL;
3833 iter_get_mem(struct module_env* env, int id)
3835 struct iter_env* ie = (struct iter_env*)env->modinfo[id];
3838 return sizeof(*ie) + sizeof(int)*((size_t)ie->max_dependency_depth+1)
3839 + donotq_get_mem(ie->donotq) + priv_get_mem(ie->priv);
3843 * The iterator function block
3845 static struct module_func_block iter_block = {
3847 &iter_init, &iter_deinit, &iter_operate, &iter_inform_super,
3848 &iter_clear, &iter_get_mem
3851 struct module_func_block*
3852 iter_get_funcblock(void)
3858 iter_state_to_string(enum iter_state state)
3862 case INIT_REQUEST_STATE :
3863 return "INIT REQUEST STATE";
3864 case INIT_REQUEST_2_STATE :
3865 return "INIT REQUEST STATE (stage 2)";
3866 case INIT_REQUEST_3_STATE:
3867 return "INIT REQUEST STATE (stage 3)";
3868 case QUERYTARGETS_STATE :
3869 return "QUERY TARGETS STATE";
3870 case PRIME_RESP_STATE :
3871 return "PRIME RESPONSE STATE";
3872 case COLLECT_CLASS_STATE :
3873 return "COLLECT CLASS STATE";
3874 case DSNS_FIND_STATE :
3875 return "DSNS FIND STATE";
3876 case QUERY_RESP_STATE :
3877 return "QUERY RESPONSE STATE";
3878 case FINISHED_STATE :
3879 return "FINISHED RESPONSE STATE";
3881 return "UNKNOWN ITER STATE";
3886 iter_state_is_responsestate(enum iter_state s)
3889 case INIT_REQUEST_STATE :
3890 case INIT_REQUEST_2_STATE :
3891 case INIT_REQUEST_3_STATE :
3892 case QUERYTARGETS_STATE :
3893 case COLLECT_CLASS_STATE :